Amivantamab in Participants With Advanced NSCLC and MET Exon 14 Skipping Mutations: Final Results From the CHRYSALIS Study

INTRODUCTION: Amivantamab is an EGFR-MET bispecific antibody with immune cell-directing activity. We assessed the safety and efficacy of amivantamab in participants with advanced NSCLC harboring primary MET exon 14 skipping mutations (METex14). METHODS: CHRYSALIS enrolled participants with METex14 NSCLC who progressed after or declined standard-of-care therapy. Participants received intravenous amivantamab weekly for 4 weeks and biweekly thereafter. Objective response rate, duration of response (DoR), clinical benefit rate, progression-free survival, overall survival, safety, and circulating tumor DNA were analyzed. RESULTS: Among 97 participants, 16 were treatment naive, 28 received prior treatment without MET therapies, and 53 received prior MET therapies. Objective response rate was 32% overall, 50% in treatment-naive participants, 46% in participants without prior MET therapies, and 19% in participants with prior MET therapies. In participants without prior MET therapies, amivantamab activity was observed regardless of co-occurring genomic alterations. Clinical benefit rate was 69% overall, 88% in treatment-naive participants, 64% in participants without prior MET therapies, and 66% in participants with prior MET therapies. Median DoR was 11.2 months; 61% (19/31) of the responders had DoR greater than or equal to 6 months. Median progression-free survival was 5.3 months (95% confidence interval, 4.3-7.0); median overall survival was 15.8 months (95% confidence interval, 14.6-not estimable). Most common adverse events were rash (79%) and infusion-related reactions (72%), most being grades 1 to 2 (52%). CONCLUSIONS: The safety profile was consistent with previous reports of amivantamab in EGFR-mutant NSCLC. Amivantamab demonstrated clinically meaningful and durable antitumor activity in participants with METex14 advanced NSCLC, including those who progressed on prior MET therapies.