Amgen trumpets T-Vec oncolytic virus results from PhIII melanoma study

CHICAGO--Amgen ($AMGN) took another big step forward on its march to a potential approval for talimogene laherparepvec, the oncolytic virus known as T-Vec, which is designed to invade tumor cells and then cause them to self-destruct while triggering an immune assault on the cancer. Interim results from Amgen's Phase III trial demonstrated the drug's ability to shrink tumors while delivering some early signs of improved survival rates for melanoma patients.

T-Vec is a re-engineered herpes simplex virus which replicates in tumor tissue, rupturing the membranes of cancer cells while amping up the white blood cell growth factor GM-CSF. The Phase III data show a 16% durable response rate--compared to only 2% for the GM-CSF arm of the study--with a 26% overall response rate (6% for GM-CSF). "A trend toward overall survival (HR = 0.79, 95 percent CI, 0.61-1.02) was also observed at a predefined interim analysis," says Amgen.

"These are the first data from a controlled trial of oncolytic immunotherapy to demonstrate activity in melanoma," said R&D chief Sean Harper.

The pioneering approach looks positive for a minority of the patients with melanoma, but Amgen is now exploring the idea of combining T-Vec with a PD-1 approach, with several experimental projects under way that have demonstrated some strong indications of its impact on the immune system. 

"Scientifically, it's a compelling idea to combine T-Vec with a PD-1," Amgen's David Chang, who oversees the T-Vec program, told Adam Feuerstein at TheStreet. "We're doing early safety studies, it's too early to comment but the interest in pursuing this approach is much higher today."

Amgen bought T-Vec along with all of BioVex--a 2009 Fierce 15 company--in a $1 billion deal orchestrated by Roger Perlmutter when he was in charge of R&D. Now his successor has tapped this late-stage effort as one of the company's top prospects in the clinic. Several analysts have been waiting for overall survival data, though, before they're willing to predict its success on the market.

"With today's reported interim results, we believe the probability of success for T-Vec demonstrating an OS benefit at final data later this year should increase although more modestly given previous reports of favorable OS trend," ISI's Mark Schoenebaum wrote over the weekend. "Admittedly, T-Vec's role in a subset of advanced melanoma patients as an injectable (injected directly into the tumor) is becoming less clear with increasing competition in the melanoma space, such as the development of PD-1 antibodies."

- here's the press release
- here's the story from TheStreet

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