The US Food and Drug Administration (FDA) approved the supplemental Biologics License Application (sBLA) for panitumumab, a fully humanized monoclonal anti-EGFR antibody, as a first-line therapy for patients with RAS wild-type metastatic colorectal cancer (mCRC).
The drug is approved as a monotherapy after treatment with oxaliplatin, fluoropyrimidine, and irinotecan-containing chemotherapy, or in combination with FOLFOX.
The FDA granted full approval for panitumumab as treatment for patients with wild-type KRAS mCRC based on evidence from the phase 3 PRIME (ClinicalTrials.gov Identifier: NCT00364013) and ASPECCT (ClinicalTrials.gov Identifier: NCT01001377) trials.
Data from a retrospective analysis of the PRIME study and the prospective, pre-defined analyses from the Phase 3 ‘0007 (ClinicalTrials.gov Identifier: NCT01412957) study led to approval of a refined indication for RAS wild-type mCRC.
The ‘0007 study compared the efficacy of panitumumab with best supportive care (BSC) with BSC alone in patients with chemorefractory, KRAS wild-type mCRC.
The secondary endpoint of the study demonstrated that patients with wild-type RAS (exons 2, 3, and 4 of KRAS and NRAS) mCRC treated with panitumumab and BSC resulted in a statistically significant prolongation in overall survival (OS) of 10 months vs 6.9 months among patients treated with BSC alone (hazard ratio [HR], 0.70; 95% CI, 0.53-0.93; P = .0135).
The FDA also approved a next generation sequencing (NGS) test that detects the RAS mutation status of patient tumor samples.
Adverse effects occurring among more than 20% of patients receiving panitumumab monotherapy included skin rash, paronychia, fatigue, nausea, and diarrhea.
- FDA approves Vectibix (panitumumab) for use in wild-type RAS metastatic colorectal cancer [news release]. Thousand Oaks, CA: PRNewswire; June 29, 2017. http://www.amgen.com/media/news-releases/2017/06/fda-approves-vectibix-panitumumab-for-use-in-wildtype-ras-metastatic-colorectal-cancer/. Accessed July 6, 2017.