Amivantamab Plus Chemotherapy Numerically Improved OS for Patients with EGFR-Mutant, Advanced NSCLC

Second Interim Analysis Results From MARIPOSA-2

According to second interim data from the MARIPOSA-2 trial, amivantamab plus chemotherapy numerically improved the overall survival (OS), and significantly prolonged the post-progression outcomes among patients with EGFR-mutant non-small cell lung cancer (NSCLC), when compared to chemotherapy alone.

The phase 3 MARIPOSA-2 study enrolled patients with EGFR-mutant (either Exon 19 deletion or L858R), advanced NSCLC who had progression on or after osimertinib therapy. Patients were randomized to receive chemotherapy (carboplatin/pemetrexed) either alone (n = 263), or with amivantamab (n = 131). The primary end point was progression-free survival (PFS), which was met at the initial analysis (hazard ratio [HR], 0.48; P < .001). At the first interim analysis of OS, there was a favorable trend seen with amivantamab plus chemotherapy vs chemotherapy alone (HR, 0.77); 95% confidence interval [CI], 0.49 to 1.21). At this second interim report, OS was analyzed, along with other end points such as time to treatment discontinuation, time to subsequent therapy, and PFS after first subsequent therapy (PFS2).

At a median follow-up duration of 18.1 months, the median OS with amivantamab plus chemotherapy was 17.7 months vs 15.3 with chemotherapy alone, representing a numerical improvement. However, the benefit did not reach the prespecified threshold for significance. The 80-month OS rate was 50% and 40%, respectively. This OS benefit was generally consistent across prespecified subgroups. Time to discontinuation and time to subsequent therapy were both prolonged with amivantamab plus chemotherapy. The median PFS2 in the amivantamab plus chemotherapy arm was 16.0 months vs 11.6 months in the chemotherapy alone group, representing a significant improvement. 

Study authors concluded that the combination of amivantamab plus chemotherapy “numerically improved OS and significantly prolonged post-progression outcomes” when compared to chemotherapy in this patient population.

Source:

Popat Sanjay, Reckamp KL, Califano R, et al. Amivantamab plus chemotherapy in EGFR-mutated, advanced non-small cell lung cancer after disease progression on osimertinib: Second interim overall survival from MARIPOSA-2. Presented at 2024 ESMO Congress. September 13-17, 2024; Barcelona, Spain.