shares surged past their 52-week high Monday after data from two small, mid-stage studies on an experimental vaccine for patients with aggressive brain tumors were presented at the American Society of Clinical Oncology in Chicago.
The studies -- dubbed ACT II and Activate -- looked at CDX-110 for glioblastoma multiforme (GBM), the most common form of primary brain tumor.
The median survival for the 23-patient ACT II study has yet to be met. But the companies said preliminary results suggest the vaccine will result in median overall survival of 33.1 months. A historical control group had an overall survival of 14.3 months. The median time to tumor progression was also longer than a historical control group -- 16.6 months, vs. 6.4 months.
In the phase II Activate trial, which included 21 newly diagnosed patients who had their tumors surgically removed and underwent radiation therapy, patients taking CDX-110 had an average overall survival of 26 months, vs. 15.2 months in patients who took standard therapy alone, according to the companies.
The vaccine was generally well-tolerated with primary toxicity reported as local injection site reactions, in both studies, according to the companies.
"So far it's encouraging to see ACT II replicate Activate, and basically double both time-to-progression and (projected) overall survival in comparison to the historical control.," said Brean Murray & Co. analyst Jonathan Aschoff, who has a buy rating and a $24 price target on the stock. Aschoff says to keep in mind that these are only small, single-arm studies. But, he says, among the positives are that in ACT II every patient showed an immune response and the company has used an optimized chemotherapy dose to best fit with the vaccine.
obtained an exclusive worldwide license to CDX-110 earlier this year. Avant is currently enrolling ACT III, a randomized, 375-patient mid- to late-stage pivotal trial on the vaccine.
Aschoff says the 90-patient portion of the phase IIb/III trial on the vaccine should be enrolled by the end of 2008, but that Pfizer may elect not to release interim disease progression data in order to proceed more swiftly and not incur a statistical penalty.
There are an estimated 10,000 new cases of GBM annually in the U.S., according to the companies.
Avant shares surged $3.97, or 28%, to $17.98. Pfizer's shares were unaffected, falling 18 cents, or 0.9%, to $19.18.