Amgen’s biologic Vectibix has hit the primary goal of a Phase III trial boosting overall survival in patients with metastatic colorectal cancer who have failed to respond to chemotherapy compared to best supportive care.

The statistically significant survival improvement was observed in patients with wild-type KRAS (exon 2) forms of the disease, but OS was also extended in those with wild-type RAS disease taking the drug, a key secondary target of study.

In another plus point, no new safety signals for Vectibix (panitumumab) were observed during the trial, the firm said. The drug already carries a boxed warning for dermatologic toxicity, which affects around 90% of patients, while other known side effects include electrolyte disturbances, diarrhoea and dehydration, interstitial lung disease, and pulmonary embolism.  

Full data from the trial are to be unveiled at a medical conference later this year, but Amgen’s research and development lead Sean Harper, said the positive overall survival results “reinforce the importance of KRAS and RAS biomarkers in making treatment decisions in metastatic colorectal cancer”.

Vectibix is the first fully human anti-EGFR antibody approved by the US Food and Drug Administration for the treatment of mCRC. 

The drug first hit the US market in 2006 as a monotherapy for EGFR-expressing mCRC following disease progression after prior chemotherapy, and was subsequently cleared in 2014 for for use in combination with FOLFOX, as first-line treatment in patients with wild-type KRAS (exon 2) disease.