Amgen Inc. (AMGN) reported positive news from its struggling cancer drug Vectibix, but Wall Street remains focused on the next week's regulatory meeting for experimental bone drug denosumab, its future growth driver.

The Thousand Oaks, Calif., biotech's news about Vectibix comes on the back of strong second-quarter earnings, positive denosumab news and a strong run in the stock. Although it is overshadowed by the news around it, Vectibix's success in colorectal cancer - where it is already approved - may help it gain ground against rival Erbitux, sold by Eli Lilly & Co. (LLY) and Bristol-Myers Squibb Co (BMY).

"Combining this momentum with our anticipation of a positive panel vote on [denosumab in osteoporosis], we continue to recommend purchase on any weakness in front of next week," said Robert Baird & Co. analyst Chris Raymond, who has a $70 target on the shares.

Amgen recently traded up 5 cents to $60.74, after rising 16% in the last month.

The success of the latest trial increases confidence that a second trial - also combining Vectibix with chemotherapy and expected by the end of September - will succeed in colorectal cancer patients that failed prior therapy.

The latest trial showed success in delaying disease progression in newly diagnosed patients without a mutation in the KRAS gene - which occurs in about 40% of colorectal cancer patients. Analysis of past studies of Vectibix and Erbitux, both so-called EGFR inhibitors, has shown they are ineffective in such patients.

To the frustration of Wall Street, Amgen hasn't detailed any data from the study, but many expect Vectibix to show effectiveness that is similar to Erbitux. Details will be released later this year at a medical meeting, Amgen said.

These trials are expected to help Amgen market the drug in earlier lines of therapy, and Lazard Capital Markets projects Vectibix sales rising from $244 million in 2009 to $465 million in 2011.

Vectibix was approved in 2006, more than two years after Erbitux, but sales have struggled since Amgen discontinued a colorectal cancer trial in 2007 after seeing a higher death rate in those on the drug. The study used Vectibix with Roche Holding AG's (RHHBY) Avastin, along with a chemotherapy regimen.

Sales of Vectibix in the U.S. dropped 36% in 2008 to $108 million, while Erbitux sales rose 8% to $739 million.

While Vectibix may see growth in coming years, Amgen investors remain focused on denosumab, forecast to bring in billions of dollars in new sales if it is approved by the FDA in October.

The widely expected approval would be for osteoporosis and bone loss caused by hormone treatment in patients with breast or prostate cancer. The company plans to eventually file for approval in reducing bone-related complications in cancer spread to the bone.

In considering its application, the FDA is asking a panel of outside medical experts to evaluate the drug - typical for new types of therapies - and vote on whether it should be approved. The FDA usually follows the advice of such panels, although it isn't required to.

A spokeswoman said Amgen can't speculate on the focus of the panel.

The panel, scheduled for Aug. 13, will likely focus on effectiveness and side effects of the drug, which has the support of six Phase III trials involving more than 11,000 patients, with a relatively clean safety profile.

But quick success isn't guaranteed. Last year, a similar FDA panel backed Pfizer Inc.'s (PFE) proposed osteoporosis drug, Fablyn, but it is yet to reach the market after receiving a "complete response" letter from the agency seeking additional information in January.

-Thomas Gryta; Dow Jones Newswires; 212-416-2169; thomas.gryta@dowjones.com