Avacta
Announces Promising Early Efficacy and
Safety Data for AVA6000 in the Phase 1a Dose Escalation and
Ongoing Enrollment in the Phase 1b Expansion
Cohorts
Encouraging Progression Free Survival (PFS) data observed in
patients with salivary gland cancers compared to conventional
treatments
LONDON AND PHILADELPHIA - 07 March
2025 - Avacta Therapeutics (AIM: AVCT), a life sciences company
developing next generation peptide drug conjugates (PDC) targeting
powerful anti-tumor payloads directly to the tumor, is pleased to
announce that the lead program of the Company, AVA6000, the first
clinical stage asset which is a pre|CISION®-enabled form of
doxorubicin, has completed the Phase 1a dose escalation with
encouraging PFS data in patients with salivary gland
cancers.
The Company has initiated enrollment
in the Phase 1b expansion cohorts with multiple patients
treated.
Promising early efficacy and safety
signals are observed in the Phase 1a trial. As of the most recent
data cut-off, the favorable safety profile continues to be observed
when compared with conventional dose doxorubicin, including no
observed events of severe cardiac toxicity, which are associated
with conventional doxorubicin.
Among patients in the
dose-escalation portion, 11 patients with salivary gland cancers
have been treated with AVA6000 at or above the dose of 250
mg/m2 and above. Among these 11 patients, one patient
experienced a confirmed partial response as best response (greater
than -30% reduction in tumor diameters by RECIST criteria), four
patients had minor responses (-10 to -29% reduction by RECIST
criteria), and only one patient had disease progression for a
disease control rate of 91%. These responses have been durable to
date. Importantly, the median PFS has not yet been reached, as five
patients remain on AVA6000 treatment and 9 of the 11 patients are
without progression and remain in follow-up. The median time of
follow-up in this cohort is approximately 5 months. These data
compare very favorably to published PFS reports (with conventional
anti-cancer therapy) in this setting of pre-treated SGC, is
reported at approximately 3.5 months. It is anticipated that PFS
would be the primary endpoint in the registrational trial of
AVA6000 in this indication, which is characterized by low response
rates and high unmet need.
Avacta also announces patient dosing
in the AVA6000 Phase 1b expansion cohorts with multiple patients
treated in this portion of the trial, which include three
indications: (1) salivary gland cancer, (2) triple negative breast
cancer and (3) high grade soft tissue sarcoma. Each arm
of the Phase 1b expansion cohort will enroll 20-30 patients by the
following criteria.
·
Salivary gland
cancers: patients with advanced or
metastatic salivary gland cancers of any histologic subtype.
Patients may have received up to 1 prior line of therapy in the
metastatic or advanced setting.
·
Triple negative
breast cancer: patients with
advanced or metastatic triple negative breast cancer with up to 2
prior lines of therapy in the metastatic or advanced
setting
·
High grade soft
tissue sarcomas: patients with
undifferentiated pleomorphic sarcoma or dedifferentiated
liposarcoma and patients may have received 0 or 1 prior line of
therapy in the metastatic or advanced setting
The Company anticipates providing a
further update from the Phase 1a dose escalation data in 2Q 2025
and Phase 1b dose expansion cohort data at the end of 2025. The
full Phase 1a data will be presented in 2H 2025, including a full
assessment of the cardiac safety data with long-term follow
up. The data will allow the Company to plan for the
registration study of AVA6000.
Alan Ho, MD PhD, Chief of the Head and Neck Oncology
Service, Memorial Sloan Kettering Cancer Center and member,
Avacta Scientific Advisory Board, commented:
"We are very excited to move the development of AVA6000 to the
next level to generate data that
demonstrates clinically meaningful efficacy and durability of
response in patients with previously treated salivary gland
cancers. It is important to note the high degree of unmet
need in this disease where few agents have shown efficacy. I
am happy to participate in the trials of AVA6000 in this disease
setting going forward."
Christina Coughlin, CEO of Avacta Therapeutics
commented:
"We are very pleased to advance to the expansion cohorts in
the AVA6000 trial in these three indications with high unmet
need. Our development of AVA6000 is proceeding according to
plans and today's new data demonstrate the durability of the
responses we have observed in the SGC indication. We believe
that AVA6000 has an important role to play in the clinic, given our
preliminary efficacy data and the large commercial market size of
conventional doxorubicin"
-Ends-
For
further information from Avacta, please contact:
About Avacta - www.avacta.com
Avacta Therapeutics is a
clinical-stage life sciences company expanding the reach of highly
potent cancer therapies with the
pre|CISION® platform.
pre|CISION® is a proprietary payload delivery
system based on a
tumor-specific protease (fibroblast activation protein or
FAP) that is designed to concentrate highly potent payloads in
the tumor microenvironment while sparing normal tissues. Our
innovative pipeline consists of pre|CISION® peptide
drug conjugates (PDC) or Affimer® drug conjugates
(AffDC) that leverage the tumor-specific release mechanism,
providing unique benefits over traditional antibody drug
conjugates.
About the pre|CISION® Platform
The pre|CISION® platform
comprises an anticancer payload conjugated to a proprietary peptide
that is a highly specific substrate for fibroblast activation
protein (FAP) which is upregulated in most solid tumors compared
with healthy tissues. The pre|CISION® platform harnesses
this tumor specific protease to cleave pre|CISION®
peptide drug conjugates and pre|CISION®
antibody/Affimer® drug conjugates in the tumor
microenvironment, thus releasing active payload in the tumor and
reducing systemic exposure and toxicity, allowing dosing to be
optimized to deliver the best outcomes for patients.
