Amgen's Vectibix scores first-line approval in wild-KRAS colorectal cancer

The FDA has OK'd the use of Amgen's ($AMGN) Vectibix as a first-line treatment for wild-type KRAS metastatic colorectal cancer. The agency approved the frontline use of the drug in combination with Folfox chemotherapy.

Vectibix was initially approved 8 years ago for solo use among patients with EGFR-expressing cases of colorectal cancer as a second-line therapy--after their disease had progressed following various chemo treatments. In a pair of late-stage trials, Amgen demonstrated that combining Vectibix with a Folfox regimen could amp up overall survival rates in patients with wild-type KRAS tumors, pushing the average OS rate from 19.4 months from the chemo-only group to 23.8 months in the combo arm.

Over the past several years, a number of drug developers have been drilling down into cancer, identifying genetically defined groups which respond best to a new wave of cancer drugs. Amgen itself took the unusual step of asking the FDA to narrow Vectibix's initial colorectal approval to patients without a KRAS gene mutation. In several studies, the drug proved to be effective in patients with wild-type KRAS and not so effective in those with KRAS mutations. Along with today's new Vectibix approval, the FDA cleared a KRAS diagnostic developed by Qiagen ($QGEN).

"Vectibix is now the first approved biologic to show a significant survival benefit when combined with Folfox as a first-line treatment," said Dr. Lee Schwartzberg, medical director of The West Clinic, in a statement. "Vectibix has shown a significant benefit to patients with wild-type KRAS metastatic colorectal cancer when used with Folfox, which gives us a valuable new treatment option as we help patients fight this devastating disease." 

Vectibix brought in $389 million for Amgen last year. 

- see the release from Amgen