AVXS Avexis, Inc. (delisted)

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Continuing Employee Benefits

        Pursuant to the Merger Agreement, Parent has agreed that, from the Effective Time to December 31, 2019, it will provide or cause the Surviving Corporation to provide, to each individual who is employed by AveXis and its subsidiaries immediately prior to the Effective Time (each, an " AveXis Employee "), for so long as such AveXis Employee continues to be employed by Parent or its subsidiaries, (i) salary or wage rate and cash incentive opportunities that are each no less favorable than those provided to such AveXis Employee by AveXis or its subsidiaries immediately prior to the Effective Time and (ii) other employee benefits (excluding the value of equity compensation) that are, in the aggregate, substantially comparable to those provided to such AveXis Employee by AveXis or its subsidiaries immediately prior to the Effective Time.

        Parent has also agreed that, with respect to any employee benefit plan maintained by Parent or its subsidiaries (including any vacation, paid time-off and severance plans but excluding any defined benefit pension plans and any post-retirement medical plans), Parent shall provide each AveXis Employee with service credit for purposes of determining eligibility to participate, vesting and amount or level of benefits, subject to certain customary exclusions.

        In addition, Parent has agreed that each AveXis Employee shall be immediately eligible to participate, without any waiting time, in any and all equity plans and welfare plans of Parent and its subsidiaries on the same basis as other similarly situated employees of Parent, the Surviving Corporation and their respective affiliates and, with respect to any welfare plan maintained by Parent or any of its subsidiaries in which any AveXis Employee is eligible to participate after the Effective Time, Parent has agreed to use commercially reasonable efforts to, and cause the Surviving Corporation to:

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waive all limitations as to preexisting conditions and exclusions and waiting periods and actively-at-work requirements with respect to participation and coverage requirements applicable to such AveXis Employees and their eligible dependents and beneficiaries, to the extent such limitations were waived, satisfied or did not apply to such AveXis Employees or eligible dependents or beneficiaries under the corresponding welfare plan of AveXis or its subsidiaries in which such AveXis Employees participated immediately prior to the Effective Time, and



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provide AveXis Employees and their eligible dependents and beneficiaries with credit for any co-payments and deductibles paid prior to the Effective Time in satisfying any analogous deductible or out-of-pocket maximum requirements to the extent applicable under any such plan.

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The foregoing summary is qualified in its entirety by reference to the Merger Agreement, which is filed as Exhibit (e)(1) hereto and is incorporated herein by reference.

Annual Bonuses for Year of Closing

        Parent has also agreed that each AveXis Employee who remains employed as of December 31 of the year that includes the Effective Time shall be entitled to receive a bonus payment under the applicable annual incentive program for such year. The bonus payment will be equal to the greater of (i) such AveXis Employee's target bonus for the year and (ii) the amount that would be paid based on actual performance for such year. The bonus payment will be paid no later than March 15 of the following year. In addition, each AveXis Employee who is subject to certain qualifying terminations during the year that includes the Effective Time will receive a prorated bonus payment for the year based on target level performance.

Retention Programs

        The Merger Agreement provides that the Company may establish a retention program for newly-hired or promoted employees, which will not exceed $50 million in the aggregate, and awards under which will be cash-based awards payable no earlier than the one-year anniversary of the respective hiring or promotion date, subject to the applicable AveXis Employee's continued employment through such date or earlier upon certain qualifying terminations.

        In addition, AveXis and Parent have agreed to cooperate to establish a retention program to be implemented following the Effective Time in order to assist in the retention of key employees of AveXis. Each of the AveXis executive officers, if he or she remains employed with AveXis through the Effective Time, may be eligible to receive a retention award pursuant to such program.

        As of the date of this Schedule 14D-9, none of the AveXis executive officers has received an award under either of the retention programs described above.

Indemnification and Exculpation of Directors and Officers

        Under Section 145 of the DGCL, AveXis has broad powers to indemnify its directors and officers against liabilities they may incur in such capacities, including liabilities under the Securities Act of 1933, as amended.

        The Merger Agreement provides that all rights to indemnification and exculpation from liabilities for acts or omissions occurring at or prior to the Effective Time (and rights to advancement of expenses) in existence on the date of the Merger Agreement in favor of any person who is or prior to the Effective Time becomes, or has been at any time prior to the date of the Merger Agreement, a director, officer, employee or agent (including as a fiduciary with respect to an employee benefit plan) of AveXis, any of its subsidiaries or any of their respective predecessors (each, an " Indemnified Party ") as provided in the Fifth Amended and Restated Certificate of Incorporation of AveXis, the Amended and Restated Bylaws of AveXis, the organizational documents of any AveXis subsidiary or any indemnification agreement between such Indemnified Party and AveXis or any of its subsidiaries in effect as of the date of the Merger Agreement (i) will survive the Merger, (ii) will continue in full force and effect in accordance with their terms with respect to any claims against any such Indemnified Party arising out of such acts or omissions and (iii) will not be amended, repealed or otherwise modified in any manner that would adversely affect any right thereunder of any such Indemnified Party. Parent will ensure that the Surviving Corporation complies with and honors the foregoing obligations.

        Without limiting the above or any rights of any Indemnified Party pursuant to any indemnification agreement, from and after the acceptance for payment of, and payment by Purchaser for, any Shares pursuant to the Offer, the Surviving Corporation will indemnify and hold harmless, as and to the fullest

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extent permitted by applicable law, each such Indemnified Party against any losses, claims, damages, liabilities, costs, expenses (including reasonable attorney's fees and expenses in advance of the final disposition of any proceeding to each Indemnified Party to the fullest extent permitted by applicable law upon receipt of any undertaking required by applicable law), judgments, fines and amounts paid in settlement of or in connection with any such threatened or actual proceeding pertaining to (i) the fact that the Indemnified Party is or was a director, officer, employee or agent (including as a fiduciary with respect to an employee benefit plan) of the Company, any of its subsidiaries or any of their respective predecessors or (ii) the Merger Agreement or any of the transactions contemplated thereby, whether in any case asserted or arising before or after the Effective Time. The Merger Agreement also contains certain customary provisions regarding control of the defense and settlement of legal proceedings subject to such indemnification.

        The Merger Agreement permits AveXis to obtain, at or prior to the Effective Time, and requires Parent to maintain, prepaid (or "tail") directors' and officers' liability insurance policies in respect of acts or omissions occurring at or prior to the Effective Time (including for acts or omissions occurring in connection with the approval of the Merger Agreement and the consummation of the transactions contemplated thereby) for the period beginning upon the acceptance for payment of, and payment by Purchaser for, any Shares pursuant to the Offer and ending six years from the Effective Time, covering each Indemnified Party and containing terms (including with respect to coverage and amounts) and conditions (including with respect to deductibles and exclusions) that are, individually and in the aggregate, no less favorable to any Indemnified Party than those of AveXis' directors' and officers' liability insurance policies in effect on the date of the Merger Agreement. In the event AveXis does not obtain such "tail" insurance policies, then, for the period beginning upon the acceptance for payment of, and payment by Purchaser for, any Shares pursuant to the Offer and ending six years from the Effective Time, Parent will maintain in effect AveXis' directors' and officers' insurance policies in effect on the date of the Merger Agreement in respect of acts or omissions occurring at or prior to the Effective Time (including for acts or omissions occurring in connection with the approval of the Merger Agreement and the consummation of the transactions contemplated thereby). Notwithstanding the foregoing, neither Parent nor the Surviving Corporation will be required to pay an aggregate annual premium for such insurance policies in excess of 300% of the annual premium payable by AveXis for coverage for its current fiscal year under AveXis' directors' and officers' liability insurance policies in effect on of the date of the Merger Agreement.

Other Arrangements

        To the knowledge of AveXis, except for certain agreements described in this Schedule 14D-9 between AveXis and its executive officers and directors, no material employment, equity contribution or other agreement, arrangement or understanding between any executive officer or director of AveXis, on the one hand, and Parent, Purchaser or AveXis, on the other hand, exists as of the date of this Schedule 14D-9, and neither the Offer nor the Merger is conditioned upon any executive officer or director of AveXis entering into any such agreement, arrangement or understanding.

ITEM 4.    THE SOLICITATION OR RECOMMENDATION

Solicitation or Recommendation

        At a meeting held on April 6, 2018, after careful discussion and consideration, the Board unanimously (i) approved and declared advisable the Merger Agreement, the Offer, the Merger and the other transactions contemplated by the Merger Agreement; (ii) determined that the Offer, the Merger, and the other transactions contemplated by the Merger Agreement were fair to and in the best interests of AveXis and its stockholders; (iii) acknowledged and agreed that the Merger shall be effected under Section 251(h) of the DGCL and shall be effected as soon as practicable following the

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Acceptance Time; and (iv) resolved to recommend that the stockholders of the Company accept the Offer and tender their Shares pursuant to the Offer.

Background of the Merger Agreement; Reasons for Recommendation

Background of the Merger Agreement

         The following chronology summarizes the key meetings and events that led to the signing of the Merger Agreement. The following chronology does not purport to catalogue every conversation among the Board or the representatives of AveXis and other parties.

        The Company's management and the Board regularly review the Company's performance and prospects in light of its business and developments in the biotechnology and pharmaceutical industries. These reviews have included consideration, from time to time, of potential partnerships, collaborations and other strategic transactions to enhance stockholder value, including potential sale transactions.

        In early 2015, prior to the Company's initial public offering, the Company engaged in discussions with Company A regarding a business combination transaction with Company A. After negotiations, the Company and Company A were not able to reach agreement on the terms of a potential combination and Company A terminated discussions. None of the members of Company management at the time of these discussions have a current relationship with the Company.

        Beginning in the fall of 2016, following the Company's release of an update on interim data from its ongoing Phase 1 clinical trial of AVXS-101 for the treatment of SMA Type 1, the Company was contacted by several biotechnology and pharmaceutical companies, including Company B, to discuss the Company's business and potential opportunities for various transactions or collaborations. Over the course of the next year, the Company had general discussions from time to time with Company B and other interested biotechnology and pharmaceutical companies.

        On June 21, 2017, Mr. Sean P. Nolan, the Company's President and Chief Executive Officer, met over dinner with the Chief Executive Officer and Chief Operating Officer of Company B. At this dinner, the representatives of Company B expressed an interest in submitting an offer to acquire the Company.

        On June 29, 2017, the Company received an unsolicited letter from Company B containing a non-binding proposal to acquire 100% of the Company's equity for $112.00 per share, which offer price consisted of 40% cash and 60% Company B common stock (the " June 29 Proposal "). On June 28, 2017, the last trading day prior to the June 29 Proposal, the closing price for shares of the Company's common stock was $81.69.

        On July 7, 2017, the Board, along with representatives of Goldman Sachs & Co. LLC (" Goldman Sachs "), which had been engaged as the Company's financial advisor, and Cravath, Swaine & Moore LLP (" Cravath "), which had been engaged as outside counsel to the Company, met to discuss, among other topics, the June 29 Proposal. At the meeting, a representative of Cravath reviewed with the members of the Board their fiduciary duties and obligations in the context of an unsolicited offer to acquire the Company, as well as other legal matters, and representatives of Goldman Sachs discussed with the Board its preliminary financial analyses of the June 29 Proposal. Representatives of the Company's management reviewed with the Board the Company's key upcoming regulatory and clinical milestones relating to the approval and commercial launch of AVXS-101 and the Board considered the risks to the Company of pursuing a transaction during a critical period in the Company's regulatory review process. At this meeting, the Board discussed with the Company's senior management and the representatives of Goldman Sachs the preliminary financial model for the Company prepared by the Company's management, the Company's prospects generally, AVXS-101 and the Company's pipeline. Following discussion, the Board determined to seek improved terms from Company B as a condition to allowing Company B to conduct due diligence or otherwise further exploring a transaction, including,

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among other things, an increase in the offer price, an increase in the cash portion of the consideration and a clear understanding from Company B of the need for closing certainty and the allocation of certain regulatory and clinical risks to Company B at signing.

        On July 11, 2017, Mr. Nolan spoke telephonically with representatives of Company B and conveyed the Board's views about the necessary parameters that an offer would be required to include in order for the Board to consider engaging in a transaction with Company B or to permit Company B to conduct due diligence, including an increase in the offer price and agreement in advance on the allocation of regulatory and clinical risks to Company B upon signing of a transaction.

        On July 20, 2017, representatives of Company B called Mr. Nolan to deliver a revised proposal to acquire all of the outstanding equity of the Company for $118.00 per share, consisting of $59.00 in cash and a fixed value of $59.00 of Company B common stock (subject to a 10% symmetrical collar), which offer was subsequently delivered to the Company in writing (the " July 20 Proposal "). The July 20 Proposal also stated that Company B was prepared to assume certain clinical and regulatory risks between signing and closing.

        On July 21, 2017, the Board, along with representatives of Goldman Sachs and Cravath, met to consider and discuss the July 20 Proposal. The Board determined to seek improved terms from Company B as a condition to permitting Company B to conduct due diligence or otherwise further exploring a transaction. Following the Board meeting, Mr. Nolan spoke telephonically with representatives of Company B and explained that Company B would only be permitted to conduct due diligence if Company B improved its offer, including with respect to price, the consideration mix, the elimination of the collar on the stock portion of the consideration and closing certainty.

        On July 24, 2017, Mr. Nolan and representatives of Company B spoke telephonically regarding Company B's perspectives as to how it might improve its offer to acquire the Company. Representatives of Company B emphasized that Company B was prepared to move quickly to execute and consummate a transaction.

        On July 25, 2017, Messrs. Nolan and Dee met with representatives of Company B for dinner in Chicago. Company B's CEO stated that Company B would be willing to raise its offer price to $130.00 per share, consisting of 55% cash and 45% Company B common stock, and that the stock portion of the consideration would not be subject to a collar (the " July 25 Proposal ").

        On July 26, 2017, Mr. Nolan electronically transmitted to representatives of Company B a proposed definition of "material adverse effect" and certain other materials summarizing the Company's position on the allocation of regulatory and clinical risks in a potential transaction and indicated that alignment with Company B on approach with respect to these matters would be necessary in order for the Company to continue discussions with Company B at this stage of the Company's regulatory process. Also on July 26, 2017, the Company received a revised offer letter from Company B confirming the July 25 Proposal in which Company B confirmed that it would agree to bear certain regulatory and clinical risks upon singing of a definitive agreement.

        On July 27, 2017, the Board, along with representatives of Goldman Sachs and Cravath, met to consider and discuss the July 25 Proposal. Following the discussion, the Board determined that, in light of Company B's improved offer and indication that it would accept certain key risk allocation and transaction certainty terms, it would permit Company B to conduct limited due diligence to enable it to further improve its offer price as well as to increase the cash portion of the consideration. Following the Board meeting, Mr. Nolan conveyed the Board's decision to a representative of Company B.

        On July 28, 2017, Cravath sent a draft confidentiality agreement to Company B's legal counsel, the terms of which were negotiated over the next several days. On July 31, 2017, the Company and Company B executed the confidentiality agreement and the Company provided Company B with access to a virtual data room in order for Company B to perform its due diligence investigation. During the

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following weeks, Company B conducted its due diligence investigation of the Company and representatives of each of the Company and Company B met to discuss certain diligence items.

        On August 9, 2017, the Board held a regularly scheduled meeting at which the Company's management reviewed with the Board the status of discussions with Company B. After considering the impact of the due diligence process and transaction discussions on the Company in light of near-term clinical regulatory milestones, the Board determined to request that Company B provide improved terms by the close of business on August 16, 2017.

        On August 15, 2017, representatives of Company B informed Mr. Nolan that Company B would be unable to meet the Board's August 16, 2017 deadline for submission of a revised proposal. Following a discussion with the Board, Mr. Nolan spoke telephonically with representatives of Company B and informed them that the Board had agreed to extend the deadline for Company B to submit its final offer to August 23, 2017.

        On August 23, 2017, following several weeks of due diligence, in-person meetings and technical discussions, representatives of Company B informed Mr. Nolan that Company B had determined, in light of, among other things, the strong performance of the Company's common stock, the significant premium that would be required to acquire the Company and the stage of development of AVXS-101, to discontinue its exploration of a transaction. Company B's CEO also informed Mr. Nolan that Company B would continue to monitor the Company's performance and would be prepared to reengage following the Company's upcoming meetings with the U.S. Food and Drug Administration (the " FDA ").

        On September 29, 2017, the Company announced that the FDA had notified the Company that the Company was permitted to initiate its planned pivotal trial of AVXS-101 in spinal muscular atrophy type 1 using the intravenous formulation produced by the Company's commercial manufacturing process.

        On December 5, 2017, representatives of the Company met with the FDA for an end-of-Phase 1 meeting, the purpose of which was to review non-clinical, clinical and Chemistry, Manufacturing and Controls (CMC) data that had been generated by the Company, and to align with the FDA on next steps leading to the Company's Biologics License Application (" BLA ") submission.

        On December 13, 2017, the Company announced that the FDA had notified the Company that the Company was permitted to initiate its planned phase 1 clinical trial of AVXS-101 in spinal muscular atrophy type 2 using the intrathecal route of administration, using material produced by the Company's commercial manufacturing process.

        In December 2017, Dr. Charles Bailey, Novartis's Head of Business Development & Licensing, Neuroscience, contacted Mr. R.A. Session II, the Company's Senior Vice President, Corporate Strategy & Business Development, to make an introduction, and invited Mr. Session to meet at the upcoming JP Morgan Healthcare Conference (the " JPM Conference ") in January 2018. Although the two were unable to meet at the JPM Conference, a teleconference was arranged for February 2, 2018 with Dr. Bailey and Neil Johnston, Novartis's Global Head of Business Development & Licensing, participating from Novartis and Mr. Session participating from the Company. Mr. Johnston and Dr. Bailey outlined interest in working together with the Company and noted Novartis's commitment to gene therapy as evidenced by the recent licensing transaction with Spark Therapeutics. Mr. Session stated the Company's commitment to its development program. On February 7, 2018, in an email to Mr. Session, Mr. Johnston conveyed the interest of Dr. Vasant Narasimhan, M.D., Chief Executive Officer of Novartis, to speak with Mr. Nolan. Subsequently, a call between Dr. Narasimhan and Mr. Nolan was scheduled for February 16, 2018.

        On January 4, 2018, the Company announced alignment with the FDA on next steps toward BLA submission for AVXS-101 following the receipt of minutes from its end-of-Phase 1 meeting with the

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FDA. Following the end-of-Phase 1 meeting and this announcement, the Company received inbound interest from several companies in the biotechnology and pharmaceutical industries regarding a potential strategic transaction with the Company, including Novartis and Company C.

        On January 8, 2018, the Company and REGENXBIO Inc. (" REGENXBIO ") announced the expansion of their relationship through an amended license agreement for the development and commercialization of treatments for spinal muscular atrophy. The amended license agreement provided for, among other things, the modification of the assignment provision in the parties' original license agreement to permit assignment by the Company without REGENXBIO's consent in the event of a change of control of the Company.

        On February 12, 2018, Mr. Nolan and Dr. Brian K. Kaspar, Senior Vice President, Chief Scientific Officer of the Company, met with representatives of Company C over dinner in Rosemont, Illinois, during which the representatives of Company C indicated that Company C had a significant interest in the Company.

        On February 13, 2018, the Company engaged Centerview Partners LLC (" Centerview ") as a financial advisor to assist the Company to explore potential strategic transactions involving the Company.

        On February 16, 2018, Mr. Nolan spoke telephonically with Dr. Narasimhan and Mr. Nigel Sheail, Head of Mergers & Acquisitions and Business Development & Licensing of Novartis. Dr. Narasimhan expressed a strong interest in acquiring the Company and indicated that he had the support of Novartis's chairman to submit a proposal to acquire the Company for $190.00 per share in cash. Mr. Nolan emphasized the Company's intent to continue its focus on its business as a stand-alone company given its upcoming regulatory and clinical milestones but stated that he would provide any proposal made by Novartis to the Board for consideration.

        On February 19, 2018, the Company received an offer letter from Novartis containing a preliminary and non-binding proposal to acquire all of the outstanding shares of common stock of the Company for $190.00 per share in cash (the " February 19 Proposal "). The offer letter noted that Novartis was prepared to move quickly to announce and execute a transaction and requested a period of exclusivity to negotiate the terms of a definitive agreement.

        On February 22, 2018, the Board held a meeting with members of senior management, representatives of Cravath, and, for portions of the meeting, representatives of Goldman Sachs and Centerview, to discuss the February 19 Proposal and certain other topics. At the meeting, the representatives of Cravath reviewed with the members of the Board their fiduciary duties in the context of an unsolicited offer to acquire the Company and representatives of Goldman Sachs and Centerview reviewed with the Board their respective preliminary financial analyses of Novartis's proposal. The Board discussed its view that the Company needed to maintain its focus on its business and preparation for approval and commercial launch of AVXS-101 and the risks that consideration of a transaction could pose to the Company, including the potential for distraction at a crucial point in the regulatory process and that the potential timing of a transaction could impede the Company's ability to successfully launch AVXS-101. The Board discussed, in particular, the Company's near-term need to begin to hire a sales force to execute the launch of AVXS-101. At this meeting, the Board discussed with senior management the Company's prospects generally and assumptions relating to launch dates and pricing models in respect of AVXS-101 made by senior management. Finally, a representative of Cravath discussed with the Board potential regulatory risks relevant to the Board's consideration of a transaction with Novartis. The Board determined to engage in discussions with Novartis and seek, among other things, an increase in the offer price and a clear understanding and agreement from Novartis of the need for closing certainty and the allocation of certain regulatory, manufacturing and clinical risks to Novartis for the period between signing and closing. The Board also determined to reject Novartis' request for a period of exclusivity. The Board also directed management and

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representatives of Goldman Sachs and Centerview to engage in discussions with Company C to explore its interest in an acquisition of the Company.

        On February 28, 2018, Mr. Nolan spoke telephonically with Dr. Narasimhan. During the call, Mr. Nolan informed Dr. Narasimhan that the Board had rejected Novartis' request for a period of exclusivity, but that the Board was willing to engage in discussions with Novartis regarding a potential transaction, with the expectation that Novartis would increase its offer price following a targeted due diligence review. Mr. Nolan also informed Dr. Narasimhan about the importance to the Board of certain key risk allocation and transaction certainty terms, including with respect to Novartis's commitment to obtain regulatory approvals in respect of the transaction, and reiterated the Board's concern that discussions regarding a potential transaction could interfere with the Company's business and its preparation for approval and launch of AVXS-101. Mr. Nolan and Dr. Narasimhan also discussed certain next steps regarding the due diligence process.

        On March 1, 2018, the Company provided a confidentiality agreement to Novartis, which was negotiated over the next several days among representatives of the Company, Novartis, Cravath and Hogan Lovells US LLP, Novartis's legal counsel (" Hogan Lovells "), and executed on March 5, 2018. Also on March 1, 2018, Novartis provided a diligence request list and a number of diligence questions to the Company. Access to the Company's online data room was granted to Novartis on March 5, 2018.

        On March 6, 2018, Mr. Nolan emailed Dr. Narasimhan to emphasize the Board's view that Novartis would need to provide a high degree of closing certainty, including committing to take any and all actions required to obtain regulatory approvals in respect of a potential transaction and assuming the risk with respect to certain key regulatory and clinical developments between signing and closing of a transaction and Mr. Nolan and Dr. Narasimhan further discussed these matters telephonically on March 7, 2018.

        Also on March 6, 2018, representatives of Cravath spoke with representatives of Hogan Lovells regarding such key risk allocation and closing certainty terms.

        On March 8, 2018, representatives of Goldman Sachs and Centerview spoke telephonically with representatives of Company C, who confirmed Company C's interest in exploring a potential acquisition of the Company. Following this conversation, at the direction of the Board, representatives of Goldman Sachs and Centerview provided a confidentiality agreement to Company C, which agreement was negotiated over the next several days and executed on March 10, 2018.

        On March 9, 2018, representatives of Cravath spoke telephonically with representatives of Hogan Lovells and Freshfields Bruckhaus Deringer LLP (" Freshfields "), Novartis's outside regulatory counsel, regarding the importance of closing certainty to the Board and various regulatory considerations relevant to a potential acquisition of the Company by Novartis.

        On March 10, 2018, representatives of the Company met in-person with representatives of Novartis to discuss, among other things, the Company's manufacturing process and certain safety, efficacy, regulatory, commercial and other matters, including the Company's Rett syndrome and amyotrophic lateral sclerosis programs.

        On March 12, 2018, representatives of Cravath sent a draft merger agreement to representatives of Hogan Lovells.

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        On March 12 and 13, 2018, representatives of the Company and Novartis discussed, as part of Novartis's diligence review, various matters related to AVXS-101 clinical trials.

        In addition, during the period between March 14, 2018 and March 18, 2018, Novartis continued its diligence review of the Company. During this period, the Company continued to make available additional diligence information and materials, and representatives of the Company and Novartis conducted frequent diligence calls.

        On March 14, 2018, Mr. Nolan spoke telephonically with a representative of Company C and expressed the Board's view that, in light of the Company's upcoming clinical and regulatory milestones, a potential transaction would need to provide a high degree of closing certainty.

        On March 16, 2018, representatives of the Company met in-person with representatives of Company C to discuss, among other things, the Company's manufacturing process and certain clinical, regulatory, commercial, legal, human resources and other matters.

        On March 16, 2018, representatives of Cravath discussed with representatives of Company C's outside counsel certain key transaction terms relating to closing certainty and the allocation of certain regulatory and clinical risks between signing and closing. Following such discussion, representatives of Cravath sent a draft merger agreement to representatives of Company C's outside counsel.

        Also on March 16, 2018, representatives of Hogan Lovells sent a revised draft merger agreement to representatives of Cravath.

        On March 18, 2018, representatives of Cravath and Hogan Lovells discussed certain terms of the revised draft merger agreement provided by Hogan Lovells, including the provisions relating to closing certainty and certain risk allocation provisions that had been previously discussed among the Company, Novartis, Cravath and Hogan Lovells. Also on March 18, 2018, Mr. Michael B. Johannesen, Senior Vice President, General Counsel and Chief Compliance Officer of the Company, informed representatives of Novartis that the Company had decided to postpone a proposed site visit by Novartis of the Company's manufacturing facility and, among other things, delay further diligence in light of the lack of alignment between the Company and Novartis with respect to such closing certainty and risk allocation terms.

        During the weeks of March 19 and March 26, 2018, representatives of the Company continued to speak telephonically and meet in-person with representatives of Company C to discuss certain diligence items.

        On March 21, 2018, Mr. Nolan spoke with a representative of Company C. During the call, the representative of Company C provided a preliminary indication of interest to acquire the Company for $175.00 per share in cash and stated that Company C was investigating potential sources of additional value.

        On March 22, 2018, representatives of Company C's outside counsel sent a revised draft merger agreement to representatives of Cravath.

        On March 23, 2018, Mr. Nolan spoke telephonically with Dr. Narasimhan and Mr. Sheail to discuss certain key closing certainty and risk allocation terms proposed by Novartis, including the proposed outside date for the transaction, the commitments Novartis was prepared to make in order to obtain regulatory approvals for the transaction and the allocation of certain regulatory and clinical risks between signing and closing.

        On March 25, 2018, representatives of Cravath spoke telephonically with representatives of each of Hogan Lovells and Company C's outside counsel regarding various provisions of the draft merger agreements.

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        On March 26, 2018, representatives of Cravath sent a revised merger agreement to representatives of each of Hogan Lovells and Company C's outside counsel.

        Also on March 26, 2018, Mr. Sheail, Ms. Keren Haruvi and Mr. Augusto Lima, Global Head of Mergers & Acquisitions at Novartis and Head of Legal Transactions at Novartis, respectively, had a telephonic meeting with Mr. Johannesen and Mr. Session regarding various post-closing employee retention matters and certain matters related to the diligence process.

        On March 27, 2018, Mr. Sheail, Mr. Nolan and Mr. Johannesen held a telephonic discussion regarding certain key employees.

        On March 28, 2018, Mr. Nolan spoke telephonically with a representative of Company C. During the call, the representative of Company C provided an improved proposal to acquire the Company for $185.00 per share in cash and reiterated that Company C was investigating potential sources of additional value.

        On March 30, 2018, Mr. Nolan spoke with Dr. Narasimhan and Mr. Sheail. Dr. Narasimhan provided an improved offer price of $200.00 per share in cash and proposed, among other things, a "reverse termination fee" of 5.0%, a 3.5% Company termination fee, in each case based on the fully diluted transaction equity value calculated using the proposed offer price, and an initial outside date of eight months with a possible four month extension. During the call, Dr. Narasimhan also requested that the Company enter into an exclusivity agreement with Novartis at this stage. Mr. Nolan then informed Dr. Narasimhan and Mr. Sheail that the Company was also engaged in discussions with another counterparty regarding a potential acquisition of the Company. The parties then engaged in a discussion of the relative merits of Novartis's revised proposal, including with respect to antitrust matters and proposed outside dates.

        Also on March 30, 2018, Hogan Lovells provided a further revised draft of the merger agreement to Cravath. Additionally, representatives from Hogan Lovells and representatives from Cravath held a telephonic meeting to discuss certain terms of the transaction, including the treatment of Company employee equity awards, whether the parties would enter into exclusivity, the outside date for the completion of the transaction and the treatment of the Company's employee equity awards.

        On March 31, 2018, at the direction of Company management, representatives of Goldman Sachs and Centerview spoke telephonically with representatives of Novartis and Dyal Co. LLC, Novartis's financial advisor, and discussed, among other things, the Company's expectations regarding timing, price and certain contractual terms regarding a potential transaction. The representatives from Goldman Sachs and Centerview indicated that the potential third party bidder had recently provided a competitive proposal to acquire the Company and had committed to a "hell-or-high-water" antitrust efforts standard, and that the Company expected that a transaction with such third party would be consummated in less than three months following the execution of a definitive merger agreement. Additionally, at the direction of Company management, the Goldman Sachs and Centerview representatives stated that the Company would be seeking final proposals from Novartis and the third party bidder on April 6, 2018 and that they would be sending out a process letter on April 2, 2018 that would provide information confirming the expectation of final proposal submission, including timing requirements.

        Also on March 31, 2018, at the direction of Company management, representatives of Goldman Sachs and Centerview spoke telephonically with a representative of Company C and discussed, among other things, the Company's expectations regarding timing, the fact that Company C's latest offer price was not the highest price currently proposed and certain contractual terms.

        On April 2, 2018, the Board held a meeting with representatives of Cravath and members of senior management, and, for portions of the meeting, representatives of Goldman Sachs and Centerview. A representative of Cravath reminded the Board of its earlier discussion relating to its

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fiduciary duties and reviewed the key legal terms of the draft merger agreement with each of Novartis and Company C. The Board discussed, among other things, the ongoing process and negotiations with each of Novartis and Company C and the Company's operations and upcoming regulatory and clinical milestones. Management and representatives of Cravath also discussed with the Board the potential regulatory review process in respect of a transaction with Novartis relative to Company C.

        Also on April 2, 2018, Mr. Nolan spoke telephonically with Dr. Narasimhan regarding certain key terms contained in the draft merger agreement, including the proposed outside date for the transaction. On the same day, at the direction of Company management, representatives of Goldman Sachs and Centerview sent a process letter to each of Novartis and Company C requesting that it submit a revised draft merger agreement by April 4, 2018 and a final proposal, including offer price and a revised merger agreement, by noon Eastern Time on April 6, 2018. Later that day, representatives of Cravath provided further revised draft merger agreements to each of Hogan Lovells and Company C's outside counsel.

        In the late evening of April 2, 2018, Mr. Nolan received a phone call from a representative of Company C. The representative informed Mr. Nolan that Company C was uncomfortable increasing its offer price, especially in light of the stage of approval regarding AVXS-101.

        On April 3, 2018, representatives of Centerview spoke telephonically with a representative of Company C. The representative of Company C emphasized Company C's strong interest in an acquisition of the Company, but confirmed that Company C was not in a position to increase its offer price at this point in the Company's development stage and that Company C was therefore withdrawing from the process.

        Also on April 3, 2018, representatives of AveXis hosted a visit for representatives of Novartis at the manufacturing facility of AveXis in Libertyville, Illinois. Subject matter areas of discussion included manufacturing, quality control, engineering and health and safety.

        Also on April 3, 2018, Mr. Johannesen emailed Mr. Sheail and Mr. Lima regarding certain terms of the draft merger agreement, including the proposed outside date for the transaction.

        On April 4, 2018, representatives of Hogan Lovells sent a revised draft merger agreement to representatives of Cravath.

        On April 5, 2018, various representatives of the Company and Novartis spoke telephonically regarding certain outstanding contractual terms. On the same day, Cravath provided a revised draft of the merger agreement to Hogan Lovells.

        On April 6, 2018, the Company received a final proposal from Novartis that had been approved by Novartis' Board, which outlined the acquisition of the Company for $218.00 per share in cash and an initial outside date for the transaction of three months, subject to an increase to $225.00 per share in cash in the event Novartis decided to extend the outside date in accordance with the terms of the Merger Agreement. The final proposal also provided for a termination fee that may be required to be paid by the Company under specified circumstances, including termination of the Merger Agreement by the Company to accept a Superior Proposal, equal to $284 million and a "reverse termination fee" equal to $437 million required to be paid by Novartis under specified antitrust-related circumstances, which fee would increase by an additional $105 million to $542 million if the merger agreement is terminated within 30 calendar days after the initial outside date, by an additional $195 million to $632 million if the merger agreement is terminated between 31 and 60 calendar days after the initial outside date or by an additional $285 million to $722 million if the merger agreement is terminated more than 60 days after the initial outside date. Throughout the course of the day on this date, representatives of Hogan Lovells and representatives of Cravath discussed and exchanged comments to the draft merger agreement. At the conclusion of these discussions, the parties had agreed on the final form of merger agreement.

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        Shortly thereafter, the Board held a meeting with representatives of Cravath, and, for portions of the meeting, members of senior management and representatives of Goldman Sachs and Centerview. Representatives from Cravath reviewed with the Board their fiduciary duties as well as certain key legal terms of the Merger Agreement. Representatives from Goldman Sachs reviewed with the Board the key financial terms of the Merger Agreement and Goldman Sachs' financial analysis of the Offer Price of $218.00 per Share, and rendered to the Board Goldman Sachs' oral opinion, which was subsequently confirmed by delivery of a written opinion dated April 6, 2018, that, subject to the factors and assumptions set forth therein, the Offer Price of $218.00 per Share to be paid to the holders (other than Novartis and its affiliates) of Shares pursuant to the Merger Agreement was fair from a financial point of view to such holders. Representatives from Centerview reviewed with the Board the key financial terms of the Merger Agreement and its financial analysis of the Offer Price of $218.00 per Share, and rendered to the Board its oral opinion, which was subsequently confirmed by delivery of a written opinion dated April 6, 2018, that, based upon and subject to the various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken in preparing its opinion, the Offer Price of $218.00 per Share to be paid to the holders of Shares (other than Excluded Shares (as defined herein)) pursuant to the Merger Agreement is fair, from a financial point of view, to such holders. For a detailed discussion of Goldman Sachs' Opinion and Centerview's Opinion, please see below in "—Financial Analyses and Opinions". The written opinions delivered by Goldman Sachs and Centerview are attached to this Schedule 14D-9 as Annex A and Annex B, respectively. Following additional discussion and consideration of the Merger Agreement and the Offer, the Merger and the other transactions contemplated by the Merger Agreement, the Board unanimously (i) approved the Merger Agreement and declared that the Merger Agreement, the Offer, the Merger and the other transactions contemplated by the Merger Agreement were advisable and fair to, and in the best interests of, the Company and its stockholders and (ii) resolved to recommend that the stockholders of the Company accept the Offer and tender their shares of Company Common Stock pursuant to the Offer. The Compensation Committee of the Board also approved certain employment compensation, severance and other employee benefit arrangements with respect to the employees of the Company.

        Later in the day on April 6, 2018, Mr. Nolan called Dr. Narasimhan and Mr. Johannesen called Mr. Sheail, in each case, to inform Novartis that the Company's Board had unanimously approved and declared advisable the proposed transaction with Novartis and thereafter on April 6, 2018, the Company, Novartis, and Purchaser executed the Merger Agreement.

        Before the opening of trading on The Nasdaq Stock Market LLC (the " Nasdaq ") on April 9, 2018, the Company issued a press release announcing the execution of the Merger Agreement and the forthcoming commencement of a tender offer by Purchaser to acquire all of the outstanding Shares at the Offer Price.

        On April 17, 2018, Purchaser commenced the Offer and the Company filed this Schedule 14D-9.

Reasons for Recommendation

        In evaluating the Merger Agreement, the Offer, the Merger and the other transactions contemplated by the Merger Agreement, the Board consulted with the senior management of the Company, as well as Goldman Sachs, Centerview and Cravath. In the course of making the determination that the Merger Agreement, the Offer, the Merger and the other transactions contemplated by the Merger Agreement are advisable and fair to, and in the best interests of, the Company and its stockholders and to recommend that the Company's stockholders accept the Offer

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and tender their Shares pursuant to the Offer, the Board considered numerous factors, including the following material factors and benefits of the Offer and the Merger:

•

Offer Price; Premium to the Trading Price of AveXis Common Stock . The Board considered the fact that the Offer Price of $218.00 per Share represented a:



•

88% premium to the trading price at which the Shares closed on April 6, 2018, the last trading day before the public announcement of the Offer; and



•

72% premium to the volume weighted average price for the Shares over the 30-day period preceding the public announcement of the Offer.



•

Cash Consideration; Certainty of Value.   The Board considered the fact that the form of consideration payable to the Company's stockholders will be cash, which will provide the Company's stockholders with certainty of value and immediate liquidity, while reducing the risks associated with receiving approval to launch AVXS-101 from the FDA in the United States and similar governmental authorities in the European Union and other jurisdictions and the other risks related to the U.S. launch, as well as the market and long-term business risks related to the Company's future growth prospects.



•

No Financing Condition.   The Board considered the fact that Parent and Purchaser would have sufficient cash resources to pay the amounts required to be paid under the Merger Agreement without obtaining third-party financing and that the Transaction is not subject to a financing condition.



•

Strategic Alternatives.   The Board considered the potential benefits of exploring business combination transactions with alternative potential acquirors and the likelihood that any such parties would engage in a business combination transaction with the Company on the same timeframe as Parent and with a value and contractual terms and conditions superior to those contained in the Merger Agreement, including in respect of the allocation of risks associated with matters related to regulatory approval of the Transaction in the United States and the anticipated approval and launch in the United States of AVXS-101. The Board considered, after discussions with Goldman Sachs, Centerview and senior management, that (i) a broader outreach to potential acquirors could delay a potential transaction and cause significant disruption at a critical stage of the Company's development, putting at risk a transaction with Parent at the price and terms negotiated, (ii) management had spoken with other potential counterparties and that such potential counterparties had not submitted a final proposal regarding a strategic transaction with the Company and (iii) should any potential counterparty be interested in pursuing a transaction on terms more favorable to the Company and its stockholders than those contemplated by the Merger Agreement, such counterparty would be able to pursue such a transaction despite Parent and the Company having entered into the Merger Agreement. The Board also considered the possibility of continuing as an independent company. Based on the value, timing, risk allocation and other terms and conditions negotiated with Parent, the Board ultimately determined that the Transaction is more favorable to the Company's stockholders than any other strategic alternative reasonably available to the Company, including continuing as an independent company.



•

Goldman Sachs' and Centerview's Respective Fairness Opinions and Related Analyses.   The Board considered (i) the oral opinion of Goldman Sachs, rendered to the Board on April 6, 2018, which was subsequently confirmed by delivery of a written opinion, to the effect that, as of such date and based upon and subject to the factors and assumptions set forth therein, the Offer Price of $218.00 per Share to be paid to the holders (other than Novartis and its affiliates) of Shares pursuant to the Merger Agreement was fair from a financial point of view to such holders and (ii) the oral opinion of Centerview, which was confirmed by delivery of a written

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opinion dated April 6, 2018, that based upon and subject to the procedures followed, matters considered, and qualifications and limitations on the review undertaken by Centerview in connection with its opinion, the $218.00 per Share in cash to be paid to the holders of the outstanding Shares (other than as specified in each such opinion) pursuant to the Merger Agreement was fair, from a financial point of view, to such holders. For a detailed discussion of Goldman Sachs' Opinion and Centerview's Opinion, please see below in "—Financial Analyses and Opinions". The written opinions delivered by Goldman Sachs and Centerview are attached to this Schedule 14D-9 as Annex A and Annex B, respectively.

•

Negotiation Process.   The Board considered its belief that, after extensive negotiations, the Company obtained the highest price that Parent is willing to pay for the Company, as evidenced by the Company's ability to increase the Offer Price relative to Novartis's initial offer of $190.00 per Share. The Board considered the fact that the terms of the Offer and the Merger were the result of robust arm's-length negotiations conducted by the Company, with the knowledge and at the direction of the Board, with the assistance of experienced financial and legal advisors and in the context of a competitive process.



•

Company Material Adverse Effect.   The Board considered the provisions in the Merger Agreement that provide, among other things, that any determination by, or delay of a determination by, the FDA or any other governmental entity, or any panel or advisory body empowered or appointed thereby, or any indication that any such entity, panel or body will make any determination or delay in making any determination, with respect to the approvability, manufacturing, labeling, contents of package insert, prescribing information, risk management profile, chemistry, manufacturing and controls (CMC) matters or pre-approval inspection matters relating to any of the Company's product candidates or any products or product candidates of any competitors of the Company, or any requirement relating to the results of any pre-clinical or clinical testing being conducted by or on behalf of the Company, any of its competitors or any of their respective collaboration partners, including any requirement to conduct further clinical trials or any delayed or accelerated launch of any of the Company's product candidates or any products or product candidates of any competitors of the Company; the results of, or any data derived from, any pre-clinical or clinical testing being conducted by or on behalf of the Company, any of its competitors or any of their respective collaboration partners or any announcement thereof; increased incidence or severity of any previously identified side effects, adverse events or safety observations, or reports of new side effects, adverse events or safety observations, with respect to any of the Company's product candidates or any products or product candidates of any competitors of the Company; any recommendations, statements or other pronouncements made, published or proposed by professional medical organizations or any governmental entity or representative thereof, or any panel or advisory body empowered or appointed thereby, relating to any of the Company's product candidates or any products or product candidates of any competitors of the Company; any supply chain disruption affecting the Company's product candidates or any products or product candidates of any competitors of the Company; any determination or development relating to coverage, reimbursement or payor rules or policies applicable to, or pricing of, any of the Company's product candidates or any products or product candidates of any competitors of the Company; and the expiry, finding of invalidity or unenforceability or loss of exclusivity with respect to any patent owned or licensed by the Company and covering any of the Company's product candidates are excluded from the determination of whether a Company Material Adverse Effect (as defined and more fully described in Section 13—"The Merger Agreement; Other Agreements—The Merger Agreement—Company Material Adverse Effect" in the Offer to Purchase) has occurred that would permit Novartis to elect not to consummate the Offer.

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•

Speed of Completion.   The Board considered the anticipated timing of the consummation of the transactions contemplated by the Merger Agreement, and the structure of the transaction as a tender offer for the Shares, which, subject to the satisfaction or waiver of the applicable conditions set forth in the Merger Agreement, should allow stockholders to receive the consideration for their Shares in a relatively short time frame, followed by the Merger in which stockholders who do not validly exercise appraisal rights will receive the same consideration as received by those stockholders who tender their Shares in the Offer. The Board considered that the potential for closing in a relatively short timeframe could also reduce the amount of time in which the Company's business would be subject to the potential disruption and uncertainty pending closing. The Board also considered that in the event Novartis elects to extend the Outside Date, the Offer Price will be increased to $225.00 per Share.



•

Product Development and Regulatory Risks.   The Board considered the fact that the Company's lead product development candidate, AVXS-101, has not yet been approved by the FDA or by any similar non-U.S. regulatory body, as well as the status and prospects for the Company's current pipeline in early stages of research and development. The Board considered the risks inherent in the research, development, regulatory review and potential future commercialization of these product candidates (including AVXS-101), and the risks related to market acceptance of AVXS-101 and the Company's other product candidates, if approved, and other factors potentially impacting the revenues and profitability of biotechnology and pharmaceutical products generally.



•

Product Launch and Commercialization Risks.   The Board considered the uncertainty associated with market demand, pricing, governmental reimbursement and other factors beyond the control of the Company with respect to AVXS-101 and other product candidates in the Company's pipeline, including the fact that the Company had not yet commercialized a product to date.



•

Conditions to Consummation of the Merger; Likelihood of Closing the Merger.   The Board considered the strong likelihood that the Merger will be consummated if the Acceptance Time occurs, given that the consummation of the Merger is subject to limited additional conditions following the Acceptance Time of the Offer and that the parties elected to have the Merger Agreement be effected by Section 251(h) of the DGCL to enable consummation of the Merger as soon as practicable following the Acceptance Time without a vote of the Company's stockholders.



•

Terms of the Merger Agreement.   The Board considered the terms and conditions of the Merger Agreement, including:



•

the right of the Company, under certain circumstances and subject to certain conditions, to furnish non-public information to, and to participate in discussions with, third parties in response to certain proposals relating to alternative acquisition transactions;



•

the right of the Board, under certain circumstances and subject to certain conditions, to withdraw or modify its recommendation in favor of the Offer if the Board determines, in good faith, after consultation with outside counsel, that the failure to do so would be inconsistent with its fiduciary duties under applicable law in the following circumstances: (i) the Company receives an alternative acquisition proposal that the Board determines, in good faith, after consultation with outside counsel and a financial advisor, constitutes a superior proposal or (ii) an event, occurrence, fact or change that materially affects the Company's business, assets or operations occurs or arises after the date of the Merger Agreement that was not known or reasonably foreseeable to the Board as of the date of the Merger Agreement (or if known or reasonably foreseeable, the consequences of which were not known or reasonably foreseeable), which event, occurrence, fact or change, or consequence thereof, becomes known to the Board prior to the Acceptance Time;

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•

the belief of the Board that the $284 million termination fee, representing approximately 3.25% of the equity value of the Company at the Offer Price of $218.00 per Share, would not unreasonably deter another party with the strategic interest and financial capability from making a competing proposal for the Company;



•

the obligation of Novartis to take all actions necessary to obtain antitrust approval of the Offer, the Merger and the other transactions contemplated by the Merger Agreement (other than any action with respect to AVXS-101), including, among other things, (i) entering into settlements, undertakings or consent decrees with a regulatory authority, (ii) defending through litigation any claim challenging the Merger Agreement or the transactions contemplated thereby, including seeking to have any stay or temporary restraining order vacated or reversed, (iii) divesting or holding separate any assets or businesses of Novartis or the Company and (iv) terminating existing relationships, contractual rights or obligations of Novartis or the Company, in each case other than with respect to AVXS-101;



•

the obligation of Novartis to pay to the Company a $437 million "reverse termination fee", representing approximately 5.00% of the equity value of the Company at the Offer Price of $218.00 per Share, in connection with the termination of the Merger Agreement under specified antitrust-related circumstances, which fee increases in the event Parent elects to extend the Outside Date in accordance with the terms of the Merger Agreement; and



•

the conditions to the Offer, including the fact that the Offer is conditioned upon there being validly tendered in the Offer and "received" by the "depository" (as such terms are defined in Section 251(h) of the DGCL) and not properly withdrawn prior to the then-scheduled expiration date of the Offer that number of Shares that represents one more than 50% of the total number of Shares outstanding at the time of the consummation of the Offer, including for the purposes of this calculation, the aggregate number of Shares issuable to holders of Company stock options, Company warrants, Company restricted stock units and Company performance stock units (the " Minimum Tender Condition "), which Minimum Tender Condition, if satisfied, would demonstrate strong support by the Company's stockholders for the Transaction.



•

Appraisal Rights.   The Board considered the availability of appraisal rights under the DGCL to Company stockholders who do not tender their Shares in the Offer and comply with all of the required procedures for perfecting appraisal rights under the DGCL, including the fact that such stockholders will have the right to demand appraisal and payment of the fair value of their Shares as determined by the Delaware Court of Chancery. See "Item 8. Additional Information—Appraisal Rights" for more information.

        In reaching its determinations and recommendations described above, the Board also considered the following potentially negative factors:

•

No Participation in the Company's Future Growth or Earnings.   The Board considered that if the Offer and the Merger are consummated, stockholders of the Company will receive the Offer Price in cash and will no longer have the opportunity to participate in any future earnings or growth of the Company or the combined company or benefit from any potential future appreciation in the value of the Shares, including any value that could be achieved if the Company engages in future strategic or other transactions and/or is successful in commercializing AVXS-101 or any other product candidates.



•

Disruption of the Company's Business.   The Board considered the effect of a public announcement of the Transaction on the Company's operations, stock price and employees and its ability to attract and retain key management, sales and other personnel while the Offer and the Merger are pending and the potential adverse effects on the financial and other results of the Company and the anticipated U.S. launch of AVXS-101 as a result of that disruption.

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•

Non-Solicitation Covenant.   The Board considered that the Merger Agreement imposes restrictions on the Company's solicitation of acquisition proposals from third parties and requires the Company to provide Novartis with an opportunity to propose adjustments to the Merger Agreement prior to the Company being able to terminate the Merger Agreement and accept a superior proposal, although the Board believes this would not preclude another potential acquiror from submitting a proposal to acquire the Company.



•

Termination Fee.   The Board considered the fact that the Company must pay Novartis a termination fee of $284 million if the Merger Agreement is terminated under certain circumstances, including to accept a superior proposal, and that the amount of the termination fee is comparable to termination fees in transactions of a similar size, was reasonable, would not likely deter competing bids and would not likely be required to be paid unless the Company entered into a more favorable transaction. The Board also recognized that the provisions in the Merger Agreement relating to these fees were insisted upon by Novartis as a condition to entering into the Merger Agreement.



•

Interim Operating Covenants.   The Board considered that the Merger Agreement imposes restrictions on the conduct of the Company's business prior to the consummation of the Offer, requiring the Company to conduct its and its subsidiaries' business in the ordinary course of business, which may delay or prevent the Company from undertaking business opportunities that may arise pending completion of the Offer and the Merger.



•

Risks the Offer and the Merger May Not Be Completed.   The Board considered the possibility that the Transaction might not be consummated, including the adverse effects that a failure to consummate the Transaction could have on the Company's business, the market price for the Shares and the Company's relationships with employees, suppliers and others, including the fact that (i) the Company's directors, senior management and other employees will have expended extensive time and effort and will have experienced significant distractions from their work during the pendency of the Transaction; (ii) the Company will have incurred significant transaction costs; (iii) the market's perception of the Company's prospects could be adversely affected; and (iv) the Company's continuing business relationships may be disrupted at a crucial time in connection with the anticipated United States launch of AVXS-101.



•

Regulatory Matters.   The Board considered the regulatory approvals that would be required to consummate the Transaction and the prospects for receiving such approvals. The Board considered the fact that (i) the parties would be required to use their respective reasonable best efforts to satisfy the closing conditions relating to certain regulatory matters, including by making required filings under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, and the rules and regulations promulgated thereunder, and taking certain other necessary actions and (ii) Novartis would not be required to agree to sell, divest or otherwise convey or hold separate AVXS-101, or take other actions with respect to AVXS-101.



•

Potential Conflicts of Interest.   The Board considered the potential conflict of interest created by the fact that the Company's executive officers and directors have financial interests in the transactions contemplated by the Merger Agreement, including the Offer and the Merger, which may be different from or in addition to those of other stockholders, as more fully described in "Item 3. Past Contacts, Transactions, Negotiations and Agreements—Arrangements with Current AveXis Directors and Executive Officers".



•

Tax Treatment.   The Board considered that the receipt of the Offer Price and the consideration payable in the Merger will generally be taxable to stockholders of the Company for United States federal income tax purposes. The Board believed that this was mitigated by the fact that the entire consideration payable in the Offer and the Merger would be cash, providing adequate cash for the payment of any taxes due.

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The foregoing discussion of the factors considered by the Board is not intended to be exhaustive, but rather includes the principal factors considered by the Board. The Board collectively reached the conclusion to approve the Merger Agreement, the Offer, the Merger and the other transactions contemplated by the Merger Agreement in light of the various factors described above and other factors that the members of the Board believed were appropriate. The Board did not assign relative weights to the foregoing factors or determine that any factor was of particular importance. Rather, the Board viewed its positions and recommendation as being based on the totality of information presented to, and considered by, it. In considering the factors discussed above, individual directors may have given different weights to different factors.

Intent to Tender

        As of April 5, 2018, the directors and officers of AveXis, as a group, beneficially owned 4,246,558 Shares (excluding any Shares deliverable upon exercise or conversion of any AveXis Options, AveXis RSUs and the PBM Warrants), representing approximately 11.53% of the then-outstanding Shares. To AveXis' knowledge, after making reasonable inquiry, each of AveXis' executive officers and directors currently intends to tender or cause to be tendered all Shares held of record or beneficially by such holder pursuant to the Offer (other than Shares as to which such holder does not have discretionary authority, Shares which may be retained in order to facilitate estate and tax planning dispositions and any Shares deliverable upon exercise or conversion of AveXis Options, AveXis RSUs and the PBM Warrants).

Financial Analyses and Opinions

Opinion of Goldman Sachs

        Goldman Sachs rendered its opinion to the Board that, as of April 6, 2018, and based upon and subject to the factors and assumptions set forth therein, the $218.00 per Share to be paid to the holders (other than Novartis and its affiliates) of Shares pursuant to the Merger Agreement was fair from a financial point of view to such holders. Goldman Sachs expressed no opinion as to any Additional Per Share Consideration.

         The full text of the written opinion of Goldman Sachs, dated April 6, 2018, which sets forth assumptions made, procedures followed, matters considered and limitations on the review undertaken in connection with the opinion, is attached as Annex A. Goldman Sachs provided advisory services and its opinion for the information and assistance of the Board in connection with its consideration of the Transaction. The Goldman Sachs opinion is not a recommendation as to whether or not any holder of Shares should tender such Shares in connection with the Offer or how any holder of Shares should vote with respect to the Merger or any other matter.

        In connection with rendering the opinion described above and performing its related financial analyses, Goldman Sachs reviewed, among other things:

•

the Merger Agreement;



•

annual reports to stockholders and Annual Reports on Form 10-K of the Company for the three years ended December 31, 2017 and the Company's Registration Statement on Form S-1, including the prospectus contained therein dated February 9, 2016, relating to the initial public offering of 4,250,000 Shares;



•

certain interim reports to stockholders and Quarterly Reports on Form 10-Q of the Company;



•

certain other communications from the Company to its stockholders;



•

certain publicly available research analyst reports for the Company; and



•

certain internal financial analyses and forecasts for the Company prepared by its management, which were approved for Goldman Sachs' use by the Company and are referred to as the

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Adjusted Forecasts (for more information, see below under the caption "—Certain AveXis Forecasts" for a discussion of the Adjusted Forecasts), and certain net operating loss (" NOLs ") estimates prepared by the management of the Company, as approved for Goldman Sachs' use by the Company (the " NOL Estimates ").

        Goldman Sachs' also held discussions with members of the senior management of the Company regarding its assessment of the past and current business operations, financial condition and future prospects of the Company; reviewed the reported price and trading activity for the Shares; compared certain financial and stock market information for the Company with similar information for certain other companies the securities of which are publicly traded; reviewed the financial terms of certain recent business combinations in the healthcare industry and in other industries; and performed such other studies and analyses, and considered such other factors, as Goldman Sachs deemed appropriate.

        For purposes of rendering its opinion, Goldman Sachs, with the Company's consent, relied upon and assumed the accuracy and completeness of all of the financial, legal, regulatory, tax, accounting and other information provided to, discussed with or reviewed by, it, without assuming any responsibility for independent verification thereof. In that regard, Goldman Sachs assumed with the Company's consent that the Adjusted Forecasts and the NOL Estimates had been reasonably prepared on a basis reflecting the best currently available estimates and judgments of the management of the Company. Goldman Sachs did not make an independent evaluation or appraisal of the assets and liabilities (including any contingent, derivative or other off-balance-sheet assets and liabilities) of the Company or any of its subsidiaries and it was not furnished with any such evaluation or appraisal. Goldman Sachs has assumed that all governmental, regulatory or other consents and approvals necessary for the consummation of the Transaction will be obtained without any adverse effect on the expected benefits of the Transaction in any way meaningful to its analysis. Goldman Sachs also assumed that the Transaction will be consummated on the terms set forth in the Merger Agreement, without the waiver or modification of any term or condition the effect of which would be in any way meaningful to its analysis.

        Goldman Sachs' opinion does not address the underlying business decision of the Company to engage in the Transaction or the relative merits of the Transaction as compared to any strategic alternatives that may be available to the Company; nor does it address any legal, regulatory, tax or accounting matters. Goldman Sachs' opinion addresses only the fairness from a financial point of view to the holders (other than Novartis and its affiliates) of Shares, as of the date thereof, of the $218.00 per Share to be paid to such holders pursuant to the Merger Agreement. Goldman Sachs did not express any view on, and its opinion does not address, any other term or aspect of the Merger Agreement or the Transaction or any term or aspect of any other agreement or instrument contemplated by the Merger Agreement or entered into or amended in connection with the Transaction, including the fairness of the Transaction to, or any consideration received in connection therewith by, the holders of any other class of securities, creditors, or other constituencies of the Company; nor as to the fairness of the amount or nature of any compensation to be paid or payable to any of the officers, directors or employees of the Company, or class of such persons, in connection with the Transaction, whether relative to the $218.00 per Share to be paid to the holders (other than Novartis and its affiliates) of Shares pursuant to the Merger Agreement or otherwise. Goldman Sachs did not express any opinion as to the impact of the Transaction on the solvency or viability of the Company or Novartis or the ability of the Company or Novartis to pay their respective obligations when they come due. Goldman Sachs' opinion is necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to it as of, the date of the opinion and Goldman Sachs' assumed no responsibility for updating, revising or reaffirming its opinion based on circumstances, developments or events occurring after the date thereof. Goldman Sachs' advisory services and the opinion expressed therein were provided for the information and assistance of the Board in connection with its consideration of the Transaction and such opinion does not constitute a recommendation as to whether or not any holder of Shares should tender such Shares in connection

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with the Offer or how any holder of Shares should vote with respect to the Merger or any other matter. Goldman Sachs' opinion was approved by a fairness committee of Goldman Sachs.

        The following is a summary of the material financial analyses delivered by Goldman Sachs to the Board in connection with rendering the opinion described above. The following summary, however, does not purport to be a complete description of the financial analyses performed by Goldman Sachs, nor does the order of analyses described represent relative importance or weight given to those analyses by Goldman Sachs. Some of the summaries of the financial analyses include information presented in tabular format. The tables must be read together with the full text of each summary and are alone not a complete description of Goldman Sachs' financial analyses. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before April 5, 2018, the last trading day before the date of Goldman Sachs' opinion, and is not necessarily indicative of current market conditions.

        Historical Stock Trading Analysis.     Goldman Sachs reviewed the historical intraday trading prices for the Shares for the 52-week period ended April 5, 2018. Goldman Sachs noted that, during this time period, the intraday trading price of the Shares ranged from a low of $65.23 to a high of $138.46.

        In addition, Goldman Sachs analyzed the $218.00 per Share to be paid to holders of Shares pursuant to the Merger Agreement in relation to the closing price of $119.60 on April 5, 2018, the last trading day before the date of Goldman Sachs' opinion, and the 30-day volume weighted average trading price of $127.72 per Share during the one-month period ending on April 5, 2018.

        This analysis indicated that the $218.00 per Share to be paid to the Company's stockholders pursuant to the Merger Agreement represented:

•

a premium of 82% to the closing price of $119.60 per Share on April 5, 2018; and



•

a premium of 71% to the 30-day volume weighted average price of $127.72 per Share during the one-month period ending on April 5, 2018.

        Illustrative Discounted Cash Flow Analysis.     Using the Adjusted Forecasts and the NOL Estimates, Goldman Sachs performed an illustrative discounted cash flow analysis of the Company. Using discount rates ranging from 10.5% to 12.5%, reflecting estimates of the Company's weighted average cost of capital, Goldman Sachs discounted to present value as of March 31, 2018 (i) estimates of unlevered free cash flow for the Company for the years 2018 through 2029 as reflected in the Adjusted Forecasts and (ii) a range of illustrative terminal values for the Company, which were calculated by applying perpetuity growth rates ranging from 1.0% to 3.0%, to a terminal year estimate of the free cash flow to be generated by the Company, as reflected in the Adjusted Forecasts. Goldman Sachs derived such discount rates by application of the capital asset pricing model, which requires certain company-specific inputs, including a company's target capital structure weightings, the cost of long-term debt, after-tax yield on permanent excess cash, if any, future applicable marginal cash tax rate and an estimated beta for a company, as well as certain financial metrics for the United States financial markets generally. The range of perpetuity growth rates was estimated by Goldman Sachs utilizing its professional judgment and experience, taking into account the Adjusted Forecasts and market expectations regarding long-term real growth of United States gross domestic product and inflation. In addition, using a discount rate of 11%, reflecting an estimate of the Company's cost of equity, Goldman Sachs discounted to present value as of March 31, 2018 the estimated benefits of the Company's NOLs, for the years 2018 through 2029, as reflected in the NOL Estimates. Goldman Sachs derived such discount rate by application of the capital asset pricing model, which requires certain company-specific inputs, including a beta for the company, as well as certain financial metrics for the United States financial markets generally. Goldman Sachs derived ranges of illustrative enterprise values for the Company by adding the ranges of present values described above. Goldman Sachs then added to the range of illustrative enterprise values it derived for the Company the net cash of the Company as of March 31, 2018, which was provided by the management of the Company, to derive a range of illustrative equity

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values for the Company. Goldman Sachs then divided the range of illustrative equity values it derived by the number of fully diluted outstanding shares of the Company, calculated using the treasury stock method and data provided by the management of the Company, to derive a range of illustrative present values per Share ranging from $106.26 to $146.49.

        Premia Analysis.     Goldman Sachs reviewed and analyzed, using publicly available information, the acquisition premia for certain transactions announced between January 1, 2012 and April 5, 2018 involving targets that were public, late-stage biotechnology companies and where the disclosed transaction values were between $5 billion and $12 billion.

        For the transactions above, using publicly available information, Goldman Sachs calculated the high, mean, median and low transaction premium to the target's last undisturbed or one-day prior to announcement of the transaction closing share price. This analysis indicated a high premium of 136%, a mean premium of 63%, a median premium of 53% and a low premium of 29% across the period. Using this analysis, Goldman Sachs applied a reference range of illustrative premiums of 50% to 90% to the undisturbed closing price per Share of $119.60 as of April 5, 2018 and calculated a range of implied equity values per Share of $179.40 to $227.24.

        General.     The preparation of a fairness opinion is a complex process and is not necessarily susceptible to partial analysis or summary description. Selecting portions of the analyses or of the summary set forth above, without considering the analyses as a whole, could create an incomplete view of the processes underlying Goldman Sachs' opinion. In arriving at its fairness determination, Goldman Sachs considered the results of all of its analyses and did not attribute any particular weight to any factor or analysis considered by it. Rather, Goldman Sachs made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of its analyses. No company or transaction used in the above analyses as a comparison is directly comparable to the Company, Novartis or the Transaction.

        Goldman Sachs prepared these analyses for purposes of providing its opinion to the Board as to the fairness from a financial point of view of the $218.00 per Share to be paid to the holders (other than Novartis and its affiliates) of Shares. These analyses do not purport to be appraisals nor do they necessarily reflect the prices at which businesses or securities actually may be sold. Analyses based upon forecasts of future results are not necessarily indicative of actual future results, which may be significantly more or less favorable than suggested by these analyses. Because these analyses are inherently subject to uncertainty, being based upon numerous factors or events beyond the control of

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the parties or their respective advisors, none of the Company, Novartis, Goldman Sachs or any other person assumes responsibility if future results are materially different from those forecast.

        The Offer Price was determined through arm's-length negotiations between the Company and Novartis and was approved by the Board. Goldman Sachs did not recommend any specific consideration to the Company or its Board or that any specific consideration constituted the only appropriate consideration for the Transaction.

        As described above, Goldman Sachs' opinion to the Board was one of many factors taken into consideration by the Board in making its determination to approve the Merger Agreement. The foregoing summary does not purport to be a complete description of the analyses performed by Goldman Sachs in connection with its fairness opinion and is qualified in its entirety by reference to the written opinion of Goldman Sachs attached as Annex A.

        Goldman Sachs and its affiliates are engaged in advisory, underwriting and financing, principal investing, sales and trading, research, investment management and other financial and non-financial activities and services for various persons and entities. Goldman Sachs and its affiliates and employees, and funds or other entities they manage or in which they invest or have other economic interests or with which they co-invest, may at any time purchase, sell, hold or vote long or short positions and investments in securities, derivatives, loans, commodities, currencies, credit default swaps and other financial instruments of the Company, Novartis, any of their respective affiliates and third parties, or any currency or commodity that may be involved in the transaction contemplated by the Merger Agreement for the accounts of Goldman Sachs and its affiliates and employees and their customers. Goldman Sachs acted as a financial advisor to the Company in connection with, and participated in certain of the negotiations leading to, the Transaction. Goldman Sachs has provided certain financial advisory and/or underwriting services to the Company and/or its affiliates from time to time for which its Investment Banking Division has received, and may receive, compensation, including having acted as bookrunner in connection with the Company's public offering of 4,250,000 Shares in September 2016; bookrunner in connection with the Company's public offering of 3,575,000 Shares in June 2017; and lead bookrunner in connection with the Company's public offering of 3,921,600 Shares in January 2018. Goldman Sachs also has provided certain financial advisory and/or underwriting services to Novartis and/or its affiliates from time to time for which its Investment Banking Division has received, and/or may receive, compensation including having acted as joint bookrunner in connection with the public offering by Novartis of its 3.100% Guaranteed Global Notes due 2027, 2.400% Guaranteed Global Notes due 2022 and 1.800% Guaranteed Global Notes due 2020 (aggregate principal amount $3,000,000,000) in February 2017; and having acted as financial advisor to Novartis in connection with the pending sale of its 36.5% stake in its Consumer Healthcare joint venture to GlaxoSmithKline announced in March 2018. During the two-year period ended April 6, 2018, Goldman Sachs has recognized compensation for financial advisory and/or underwriting services provided by its Investment Banking Division to Novartis and/or its affiliates of approximately $1.3 million. Goldman Sachs may also in the future provide investment banking services to the Company, Novartis and their respective affiliates for which the Investment Banking Division of Goldman Sachs may receive compensation.

        The Board selected Goldman Sachs as its financial advisor because it is an internationally recognized investment banking firm that has substantial experience in transactions similar to the Transaction. Pursuant to a letter agreement dated February 21, 2018, the Company engaged Goldman Sachs to act as its financial advisor in connection with the possible sale of all or a portion of the Company. The engagement letter between the Company and Goldman Sachs provides for fees for Goldman Sachs' services in connection with the Transaction, all of which are contingent upon consummation of the Transaction and are estimated to be approximately $48.0 million, and the Company has agreed to reimburse certain of Goldman Sachs' expenses arising, and indemnify it against certain liabilities that may arise, out of its engagement.

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Opinion of Centerview

        The Company retained Centerview as a financial advisor to the Company in connection with the Transaction. In connection with this engagement, the Board requested that Centerview evaluate the fairness, from a financial point of view, to the holders of Shares (other than (i) Shares that are owned by the Company, Parent, Purchaser, any other subsidiary of Parent or any subsidiary of the Company and (ii) Shares that are outstanding immediately prior to the effective time of the Merger and that are held by any person who is entitled to demand and properly demands appraisal of such Shares pursuant to, and who complies in all respects with, Section 262 of the DGCL (the Shares referred to in clauses (i) and (ii), together with any Shares held by any affiliate of the Company or Parent, " Excluded Shares ") of the $218.00 per Share in cash, without interest, to be paid to such holders pursuant to the Merger Agreement. On April 6, 2018, Centerview rendered to the Board its oral opinion, which was subsequently confirmed by delivery of a written opinion dated April 6, 2018 that, as of such date and based upon and subject to the various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion, the $218.00 per Share in cash proposed to be paid to the holders of Shares (other than Excluded Shares) pursuant to the Merger Agreement was fair, from a financial point of view, to such holders. Centerview expressed no view or opinion as to any Additional Per Share Consideration.

        The full text of Centerview's written opinion, dated April 6, 2018, which describes the various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion, is attached as Annex B and is incorporated herein by reference. The summary of the written opinion of Centerview set forth below is qualified in its entirety to the full text of Centerview's written opinion attached as Annex B. Centerview's financial advisory services and opinion were provided for the information and assistance of the Board (in their capacity as directors and not in any other capacity) in connection with and for purposes of its consideration of the Transaction and Centerview's opinion addressed only the fairness, from a financial point of view, as of the date thereof, to the holders of Shares (other than Excluded Shares) of the $218.00 per Share in cash to be paid to such holders pursuant to the Merger Agreement. Centerview's opinion did not address any other term or aspect of the Merger Agreement or the Transaction and does not constitute a recommendation to any stockholder of the Company as to whether or not such holder should tender Shares in connection with the Offer or otherwise act with respect to the Transaction or any other matter.

         The full text of Centerview's written opinion should be read carefully in its entirety for a description of the various assumptions made, procedures followed, matters considered, and qualifications and limitations upon the review undertaken by Centerview in preparing its opinion.

        In connection with rendering the opinion described above and performing its related financial analyses, Centerview reviewed, among other things:

•

a draft of the Merger Agreement dated April 6, 2018, referred to in this summary of Centerview's opinion as the " Draft Merger Agreement ";



•

Annual Reports on Form 10-K of the Company for the years ended December 31, 2017, December 31, 2016 and December 31, 2015;



•

certain interim reports to stockholders and Quarterly Reports on Form 10-Q of the Company;



•

certain publicly available research analyst reports for the Company;



•

certain other communications from the Company to its stockholders; and



•

certain internal information relating to the business, operations, earnings, cash flow, assets, liabilities and prospects of the Company, including the Adjusted Forecasts, and which are collectively referred to in this summary of Centerview's opinion as the " Internal Data ".

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        Centerview also participated in discussions with members of the senior management and representatives of the Company regarding their assessment of the Internal Data. In addition, Centerview reviewed publicly available financial and stock market data for the Company and compared that data with similar data for certain other companies, the securities of which are publicly traded, in lines of business that Centerview deemed relevant. Centerview also compared certain of the proposed financial terms of the Transaction with the financial terms, to the extent publicly available, of certain other transactions that Centerview deemed relevant, and conducted such other financial studies and analyses and took into account such other information as Centerview deemed appropriate.

        Centerview assumed, without independent verification or any responsibility therefor, the accuracy and completeness of the financial, legal, regulatory, tax, accounting and other information supplied to, discussed with, or reviewed by Centerview for purposes of its opinion and, with the Company's consent, Centerview relied upon such information as being complete and accurate. In that regard, Centerview assumed, at the Company's direction, that the Internal Data (including, without limitation, the Adjusted Forecasts) were reasonably prepared on bases reflecting the best currently available estimates and judgments of the management of the Company as to the matters covered thereby and Centerview relied, at the Company's direction, on the Internal Data for purposes of Centerview's analysis and opinion. Centerview expressed no view or opinion as to the Internal Data or the assumptions on which it was based. In addition, at the Company's direction, Centerview did not make any independent evaluation or appraisal of any of the assets or liabilities (contingent, derivative, off-balance-sheet or otherwise) of the Company, nor was Centerview furnished with any such evaluation or appraisal, and was not asked to conduct, and did not conduct, a physical inspection of the properties or assets of the Company. Centerview assumed, at the Company's direction, that the final executed Merger Agreement would not differ in any respect material to Centerview's analysis or opinion from the Draft Merger Agreement reviewed by Centerview. Centerview also assumed, at the Company's direction, that the Transaction will be consummated on the terms set forth in the Merger Agreement and in accordance with all applicable laws and other relevant documents or requirements, without delay or the waiver, modification or amendment of any term, condition or agreement, the effect of which would be material to Centerview's analysis or Centerview's opinion and that, in the course of obtaining the necessary governmental, regulatory and other approvals, consents, releases and waivers for the Transaction, no delay, limitation, restriction, condition or other change will be imposed, the effect of which would be material to Centerview's analysis or Centerview's opinion. Centerview did not evaluate and did not express any opinion as to the solvency or fair value of the Company, or the ability of the Company to pay its obligations when they come due, or as to the impact of the Transaction on such matters, under any state, federal or other laws relating to bankruptcy, insolvency or similar matters. Centerview is not a legal, regulatory, tax or accounting advisor, and Centerview expressed no opinion as to any legal, regulatory, tax or accounting matters.

        Centerview's opinion expressed no view as to, and did not address, the Company's underlying business decision to proceed with or effect the Transaction, or the relative merits of the Transaction as compared to any alternative business strategies or transactions that might be available to the Company or in which the Company might engage. Centerview's opinion was limited to and addressed only the fairness, from a financial point of view, as of the date of Centerview's written opinion, to the holders of the Shares (other than Excluded Shares) of the $218.00 per Share in cash to be paid to such holders pursuant to the Merger Agreement. For purposes of its opinion, Centerview was not asked to, and Centerview did not, express any view on, and its opinion did not address, any other term or aspect of the Merger Agreement or the Transaction, including, without limitation, the structure or form of the Transaction, or any other agreements or arrangements contemplated by the Merger Agreement or entered into in connection with or otherwise contemplated by the Transaction, including, without limitation, the fairness of the Transaction or any other term or aspect of the Transaction to, or any consideration to be received in connection therewith by, or the impact of the Transaction on, the holders of any other class of securities, creditors or other constituencies of the Company or any other

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party. In addition, Centerview expressed no view or opinion as to the fairness (financial or otherwise) of the amount, nature or any other aspect of any compensation to be paid or payable to any of the officers, directors or employees of the Company or any party, or class of such persons in connection with the Transaction, whether relative to the $218.00 per Share in cash to be paid to the holders of the Shares (other than Excluded Shares) pursuant to the Merger Agreement or otherwise. Centerview's opinion was necessarily based on financial, economic, monetary, currency, market and other conditions and circumstances as in effect on, and the information made available to Centerview as of, the date of Centerview's written opinion, and Centerview does not have any obligation or responsibility to update, revise or reaffirm its opinion based on circumstances, developments or events occurring after the date of Centerview' written opinion. Centerview's opinion does not constitute a recommendation to any stockholder of the Company as to whether or not such holder should tender Shares in connection with the Offer or otherwise act with respect to the Transaction or any other matter. Centerview's financial advisory services and its written opinion were provided for the information and assistance of the Board (in their capacity as directors and not in any other capacity) in connection with and for purposes of its consideration of the Transaction. The issuance of Centerview's opinion was approved by the Centerview Partners LLC Fairness Opinion Committee.

Summary of Centerview Financial Analysis

        The following is a summary of the material financial analyses prepared and reviewed with the Board in connection with Centerview's opinion, dated April 6, 2018. The summary set forth below does not purport to be a complete description of the financial analyses performed or factors considered by, and underlying the opinion of, Centerview, nor does the order of the financial analyses described represent the relative importance or weight given to those financial analyses by Centerview. Centerview may have deemed various assumptions more or less probable than other assumptions, so the reference ranges resulting from any particular portion of the analyses summarized below should not be taken to be Centerview's view of the actual value of the Company. Some of the summaries of the financial analyses set forth below include information presented in tabular format. In order to fully understand the financial analyses, the tables must be read together with the text of each summary, as the tables alone do not constitute a complete description of the financial analyses performed by Centerview. Considering the data in the tables below without considering all financial analyses or factors or the full narrative description of such analyses or factors, including the methodologies and assumptions underlying such analyses or factors, could create a misleading or incomplete view of the processes underlying Centerview's financial analyses and its opinion. In performing its analyses, Centerview made numerous assumptions with respect to industry performance, general business and economic conditions and other matters, many of which are beyond the control of the Company or any other parties to the Transaction. None of the Company, Parent, Purchaser or Centerview or any other person assumes responsibility if future results are materially different from those discussed. Any estimates contained in these analyses are not necessarily indicative of actual values or predictive of future results or values, which may be significantly more or less favorable than as set forth below. In addition, analyses relating to the value of the Company do not purport to be appraisals or reflect the prices at which the Company may actually be sold. Accordingly, the assumptions and estimates used in, and the results derived from, the financial analyses are inherently subject to substantial uncertainty. Except as otherwise noted, the following quantitative information, to the extent that it is based on market data, is based on market data as it existed on or before April 5, 2018 (the last trading day prior to the preparation of the financial analysis presented by the financial advisors at the April 6, 2018 meeting of the Board) and is not necessarily indicative of current market conditions.

Selected Public Company Analysis

        Centerview reviewed certain financial information of the Company and compared it to corresponding financial information of certain publicly traded companies that Centerview selected

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based on its experience and professional judgment (which are referred to as the "selected companies" in this summary of Centerview's opinion). Although none of the selected companies is directly comparable to the Company, the companies listed below were chosen by Centerview, among other reasons, because they are publicly traded biopharmaceutical companies with certain operational, business and/or financial characteristics that, for purposes of Centerview's analysis, may be considered similar to those of the Company.

        However, because none of the selected companies is exactly the same as the Company, Centerview believed that it was inappropriate to, and therefore did not, rely solely on the quantitative results of the selected public company analysis. Accordingly, Centerview also made qualitative judgments, based on its experience and professional judgment, concerning differences between the operational, business and/or financial characteristics of the Company and the selected companies that could affect the public trading values of each in order to provide a context in which to consider the results of the quantitative analysis.

        Using publicly available information obtained from SEC filings and other data sources as of April 5, 2018, Centerview calculated, for each selected company, the company's enterprise value (calculated as the equity value (determined using the treasury stock method and taking into account outstanding in-the-money options, warrants, restricted stock units, performance stock units and other convertible securities) plus the book value of debt and certain liabilities less cash and cash equivalents), which is referred to, with respect to the selected companies, as " Enterprise Value ".

        The selected companies are summarized below (dollars in billions):

        Based on its analysis and other considerations that Centerview deemed relevant in its professional judgment and experience, Centerview selected a reference range of Enterprise Values of $3.00 billion to $5.25 billion. In selecting this range of Enterprise Values, Centerview made qualitative judgments based on its experience and professional judgment concerning differences between the business, financial and operating characteristics of the Company and the selected companies that could affect their public trading values in order to provide a context in which to consider the results of the quantitative analysis. Applying this range of Enterprise Value and adding to it the Company's net cash and cash equivalents balance as of March 31, 2018, as set forth in the Internal Data, resulted in an implied per share equity

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value range for the Shares of approximately $92.10 to $147.50, rounded to the nearest $0.05. Centerview then compared this range to the $218.00 per Share in cash proposed to be paid to the holders of Shares (other than Excluded Shares) pursuant to the Merger Agreement.

Selected Transactions Analysis

        Centerview reviewed and compared certain information relating to the following selected biopharmaceutical transactions that Centerview, based on its experience and professional judgment, deemed relevant to consider in relation to the Company and the Transaction. These transactions were selected, among other reasons, because their participants, size or other factors, for purposes of Centerview's analysis, may be considered similar to the Transaction. Centerview used its experience, expertise and knowledge of these industries to select transactions that involved companies with certain operational, business and/or financial characteristics that, for purposes of this analysis, may be considered similar to those of the Company.

        However, because none of the selected transactions used in this analysis is identical or directly comparable to the Transaction, Centerview believed that it was inappropriate to rely solely on the quantitative results of the selected transaction analysis. Accordingly, Centerview also made qualitative judgments, based on its experience and professional judgment, concerning differences between the operational, business and/or financial characteristics of the Company and each target company as well as the Transaction and the selected transactions that could affect the transaction values of each in order to provide a context in which to consider the results of the quantitative analysis.

        Using publicly available information obtained from SEC filings and other data sources as of April 5, 2018, Centerview calculated, for each selected transaction, the transaction value (calculated as the offer value (determined using the treasury stock method and taking into account outstanding in-the-money options, warrants, restricted stock units, performance stock units and other convertible securities), plus the book value of debt and certain liabilities less cash and cash equivalents) implied for each target company based on the consideration payable in the applicable selected transaction, in each case excluding any contingent payments, which is referred to, with respect to the selected transactions, as " Transaction Value ".

        The selected transactions considered in this analysis are summarized below (dollars in billions):

        Based on its analysis and other considerations that Centerview deemed relevant in its professional judgment and experience, Centerview selected a reference range of Transaction Values of $5.25 billion to $8.5 billion. In selecting this range of Transaction Values, Centerview made qualitative judgments

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based on its experience and professional judgment concerning differences between the business, financial and operating characteristics of the Company and the target companies included in the selected transactions and other factors that could affect each transaction or other values in order to provide a context in which to consider the results of the quantitative analysis. Applying this range of Transaction Values and adding to it the Company's net cash and cash equivalents balance as of March 31, 2018, as set forth in the Internal Data, resulted in an implied per share equity value range for Shares of approximately $147.50 to $226.70, rounded to the nearest $0.05. Centerview then compared this range to the $218.00 per Share in cash proposed to be paid to the holders of Shares (other than Excluded Shares) pursuant to the Merger Agreement.

Discounted Cash Flow Analysis

        Centerview performed a discounted cash flow analysis of the Company based on the Adjusted Forecasts and the calculations of risk adjusted, after-tax unlevered free cash flows set forth in "Item 4. The Solicitation or Recommendation—Financial Analyses and Opinions—Certain AveXis Forecasts". A discounted cash flow analysis is a traditional valuation methodology used to derive a valuation of an asset or set of assets by calculating the "present value" of estimated future cash flows of the asset or set of assets. "Present value" refers to the current value of future cash flows and is obtained by discounting those future cash flows by a discount rate that takes into account macroeconomic assumptions and estimates of risk, the opportunity cost of capital, expected returns and other appropriate factors.

        In performing this analysis, Centerview calculated a range of equity values for the Company by (a) discounting to present value as of March 31, 2018 using discount rates ranging from 10.5% to 12.5% (reflecting Centerview's analysis of the Company's weighted average cost of capital) and the mid-year convention: (i) the forecasted risk adjusted, after-tax unlevered free cash flows of the Company over the period beginning on April 1, 2018 and ending on December 31, 2029 utilized by Centerview as set forth in "Item 4. The Solicitation or Recommendation—Financial Analyses and Opinions—Certain AveXis Forecasts", (ii) an implied terminal value of the Company, calculated by Centerview applying a perpetuity growth rate of 2% to the Company's after-tax unlevered free cash flows for the terminal year (as set forth in "Item 4. The Solicitation or Recommendation—Financial Analyses and Opinions—Certain AveXis Forecasts") and (iii) net present value of tax savings from usage of net operating losses and future losses and (b) adding to the foregoing results the Company's net cash and cash equivalents balance as of March 31, 2018, as set forth in the Internal Data. Centerview divided the result of the foregoing calculations by the number of fully-diluted outstanding Shares (determined using the treasury stock method and taking into account outstanding in-the-money options, warrants, restricted stock units and performance stock units) as of April 5, 2018 based on the Internal Data to derive a range of implied values per Share of approximately $109.40 to $135.85 per Share, rounded to the nearest $0.05. Centerview compared this range to the $218.00 per Share in cash to be paid to the holders of Shares (other than Excluded Shares) pursuant to the Merger Agreement.

Other Factors

        Centerview noted for the Board certain additional factors solely for informational purposes, including, among other things, the following:

•

Historical Stock Price Trading Analysis.   Centerview reviewed historical share price performance of Shares for the 52-week period ended April 5, 2018, which reflected low and high closing prices for the Shares during this 52-week period of $67.48 and $136.93.



•

Analyst Price Target Analysis.   Centerview reviewed stock price targets for the Shares in Wall Street research analyst reports publicly available as of April 5, 2018, noting these stock price targets ranged from $52.00 per Share to $171.00 per Share.

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Premia Paid Analysis.   Centerview performed an analysis of premiums paid in the selected transactions involving publicly traded biopharmaceutical companies, as set forth above in "—Summary of Centerview Financial Analysis—Selected Transactions Analysis", for which premium data was available. Centerview calculated, for each such transaction, the percentage premium represented by the transaction price per share (excluding any contingent consideration) to the target company's market price per share on the trading day prior to the first public knowledge of the possibility of the transaction, which is referred to as % premium to 1-day unaffected price. Based on the analysis above and other considerations that Centerview deemed relevant in its professional judgment, Centerview applied a range of 40% to 80% to the Company's closing stock price on April 5, 2018 (the last trading day prior to the preparation of the financial analysis presented by the financial advisors at the April 6, 2018 meeting of the Board) of $119.60, which resulted in an implied price range of approximately $167.45 to $215.30 per Share, rounded to the nearest $0.05.

General

        The preparation of a financial opinion is a complex analytical process involving various determinations as to the most appropriate and relevant methods of financial analysis and the application of those methods to the particular circumstances and, therefore, a financial opinion is not readily susceptible to summary description. In arriving at its opinion, Centerview did not draw, in isolation, conclusions from or with regard to any factor or analysis that it considered. Rather, Centerview made its determination as to fairness on the basis of its experience and professional judgment after considering the results of all of the analyses.

        Centerview's financial analyses and opinion were only one of many factors taken into consideration by the Board in its evaluation of the Transaction. Consequently, the analyses described above should not be viewed as determinative of the views of the Board or management of the Company with respect to the $218.00 per Share in cash to be paid to the holders of the Shares (other than Excluded Shares) pursuant to the Merger Agreement or any Additional Per Share Consideration or as to whether the Board would have been willing to determine that a different consideration was fair. The consideration for the Transaction was determined through arm's-length negotiations between the Company and Parent and was approved by the Board. Centerview provided advice to the Company during these negotiations. Centerview did not, however, recommend any specific amount of consideration to the Company or the Board or that any specific amount of consideration constituted the only appropriate consideration for the Transaction.

        Centerview is a securities firm engaged directly and through affiliates and related persons in a number of investment banking, financial advisory and merchant banking activities. In the two years prior to the date of its written opinion, Centerview did not provide financial advisory or other services to the Company and Centerview did not receive any compensation from the Company. In the two years prior to the date of its written opinion, Centerview provided, and is currently providing, financial advisory services to Parent unrelated to the Company and the Transaction, and Centerview did not receive any compensation from Parent. Centerview anticipates that in the future it will receive, compensation from Parent for such services. Centerview may provide financial advisory and other services to, or with respect to, the Company or Parent or their respective affiliates in the future, for which Centerview may receive compensation. Certain (i) of Centerview's and Centerview affiliates' directors, officers, members and employees, or family members of such persons, (ii) of Centerview's affiliates or related investment funds and (iii) investment funds or other persons in which any of the foregoing may have financial interests or with which they may co-invest, may at any time acquire, hold, sell or trade, in debt, equity and other securities or financial instruments (including derivatives, bank loans or other obligations) of, or investments in, the Company, Parent or any of their respective affiliates, or any other party that may be involved in the Transaction.

        The Board selected Centerview as its financial advisor in connection with the Transaction based on Centerview's reputation and experience in providing M&A advisory services to the healthcare sector. Centerview is an internationally recognized investment banking firm that has substantial experience in transactions similar to the Transaction.

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        In connection with Centerview's services as a financial advisor to the Board, the Company has agreed to pay Centerview an aggregate fee of approximately $39.2 million, $2.0 million of which was payable upon the rendering of Centerview's opinion and approximately $37.2 million of which is payable contingent upon consummation of the Transaction. In addition, the Company has agreed to reimburse certain of Centerview's expenses arising, and to indemnify Centerview against certain liabilities that may arise, out of Centerview's engagement.

Certain AveXis Forecasts

Important Information Concerning the AveXis Management Forecasts

        The Company, which does not yet have any marketed products, does not make public long-term projections as to future revenues, earnings or other results due to the unpredictability of the underlying assumptions and estimates. However, as the Company believes it is approaching FDA approval and commercial launch of its AVXS-101 product candidate, the Company began constructing a financial model to set expectations for the Company's financial performance and to provide a basis for valuing the Company.

        In connection with the Board's evaluation of the Offer and the Merger and other strategic alternatives available to AveXis, AveXis' management prepared certain unaudited prospective financial information for the years 2018 through 2029 (the " Adjusted Forecasts "). The Adjusted Forecasts were based on certain internal assumptions about the probability of success of, timing of regulatory approval and expected launch dates for, pricing and peak net sales amounts in respect of each of the Company's product candidates, other relevant factors relating to commercialization and research and development and general administrative expenses. All of these factors are difficult to predict and many are beyond AveXis' control. AveXis' management provided the Adjusted Forecasts to the Board in April 2018 for purposes of considering and evaluating Parent's acquisition proposal, and to Goldman Sachs and Centerview in connection with the rendering of Goldman Sachs' and Centerview's respective opinions to the Board and in performing their respective related financial analyses, as described above under the heading "—Financial Analyses and Opinions".

        The following is a summary of the Adjusted Forecasts:

Fiscal Year Ending December 31,
(Dollars in millions)