Encorafenib, binimetinib, and cetuximab in BRAF V600E–mutated colorectal cancer: an early post-marketing phase vigilance study

BACKGROUND: Triplet and doublet regimens of encorafenib plus cetuximab with and without binimetinib, respectively, were approved in Japan for unresectable, metastatic, BRAF V600E-mutated colorectal cancer (mCRC) that had progressed after 1–2 prior chemotherapies. This early post-marketing phase vigilance (EPPV) study collected adverse drug reactions (ADRs) from Japanese patients to ensure safety measures as appropriate. METHODS: Patients with BRAF V600E mCRC who received the triplet or doublet regimens in Japan were selected for this study. ADRs were collected as spontaneous reports between November 27, 2020 and May 26, 2021. Serious ADRs were evaluated according to guidelines of the International Council for Harmonisation and the EudraVigilance list of Important Medical Event Terms. RESULTS: An estimated 550 Japanese patients with mCRC received the triplet or doublet regimens during the 6-month EPPV period. Overall, 101 and 42 patients reported ADRs and serious ADRs, respectively. No ADRs leading to death were reported. The most frequently reported ADRs were nausea (17 patients), serous retinal detachment (16), decreased appetite (12), diarrhea (11), and vomiting (11). Among the important identified/potential risks that are defined in the risk management plans for encorafenib and binimetinib, eye disorder-related ADRs were observed in 32 patients, rhabdomyolysis-related ADRs in 12, hemorrhage-related ADRs in 7, and hepatic dysfunction-related ADRs in 7. Of 22 patients with serious eye disorders, 20 recovered or were recovering during the EPPV period. CONCLUSION: The safety profile in this EPPV study was similar to that from the phase III BEACON CRC study and no new safety concerns were identified. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10147-022-02264-z.