Amgen announced that a phase 3 study evaluating Vectibix (panitumumab) and best supportive care (BSC) met its primary endpoint, demonstrating a statistically significant improvement in overall survival (OS) in patients with chemorefractory wild-type KRAS (exon 2) metastatic colorectal cancer (mCRC) compared to those patients treated with BSC alone.

The Vectibix treatment arm further showed statistical significance for all key secondary endpoints including OS in patients with wild-type RAS (absence of mutations in exons 2, 3 and 4 of KRAS and NRAS) mCRC.

In the Vectibix treatment arm, the observed adverse events were consistent with the known Vectibix safety profile.

Full results will be submitted to a future medical congress and for publication.

"Amgen has been at the forefront of researching personalized approaches to treating cancer, and the Vectibix clinical programme continues to underscore the importance of identifying options for patients based on their cancer's genetic makeup," said Sean E. Harper, M.D., executive vice president of Research and Development at Amgen. "These positive overall survival results for Vectibix reinforce the importance of KRAS and RAS biomarkers in making treatment decisions in metastatic colorectal cancer."

Colorectal cancer is the third most common cancer worldwide, with approximately 1.2 million cases occuring globally each year. In the US, colorectal cancer is the second leading cause of cancer-related deaths, with an estimated 132,700 new cases diagnosed in 2015. In Europe, colorectal cancer is the second most common cancer, with approximately 470,000 new cases each year.

This phase 3 global, multicenter, randomized, open-label study was designed to evaluate the survival benefit of Vectibix and best supportive care (BSC) compared to BSC alone in patients with chemorefractory wild-type KRAS (exon 2) metastatic colorectal cancer (mCRC). The primary endpoint was overall survival (OS). Key secondary endpoints included progression-free survival (PFS) in patients with wild-type KRAS mCRC, as well as OS and PFS in patients with wild-type RAS (absence of mutations in exons 2, 3 and 4 of KRAS and NRAS) mCRC.

Patients were randomized 1:1 to receive 6 mg/kg of Vectibix every 14 days and BSC, or BSC alone (as defined by the investigator).

Vectibix is the first fully human anti-EGFR antibody approved by the US Food and Drug Administration (FDA) for the treatment of metastatic colorectal cancer (mCRC). Vectibix was approved in the US in September 2006 as a monotherapy for the treatment of patients with EGFR-expressing mCRC after disease progression after prior treatment with fluoropyrimidine-, oxaliplatin-, and irinotecan-containing chemotherapy.

In May 2014, the FDA approved Vectibix for use in combination with Folfox, as first-line treatment in patients with wild-type KRAS (exon 2) mCRC. With this approval, Vectibix became the first-and-only biologic therapy indicated for use with Folfox, one of the most commonly used chemotherapy regimens, in the first-line treatment of mCRC for patients with wild-type KRAS mCRC.