FDA Approval Summary: Amivantamab for the Treatment of Patients with Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations

The FDA granted accelerated approval for amivantamab-vmjw (hereafter referred to as amivantamab), a bispecific antibody directed against EGFR and mesenchymal-epithelial transition receptor, on May 21, 2021, for the treatment of adult patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) with EGFR exon 20 insertion mutations whose disease has progressed on or after platinum-based chemotherapy. Approval was based on results of an ongoing, multicenter, nonrandomized, open-label, multicohort clinical trial (CHRYSALIS, NCT02609776), demonstrating a substantial overall response rate (ORR) and durable responses, with an ORR of 40% [95% confidence interval (CI): 29-51] and a median response duration of 11.1 months (95% CI: 6.9-not evaluable). Guardant360 CDx was contemporaneously approved as a companion diagnostic for this indication to identify EGFR exon 20 insertion mutations in plasma specimens. The most notable safety finding was the high incidence (66%) of infusion-related reactions, which is addressed in both the Dosage and Administration and Warnings and Precautions sections of the product label. Other common adverse reactions (occurring in ≥20% of patients) were rash, paronychia, musculoskeletal pain, dyspnea, nausea and vomiting, fatigue, edema, stomatitis, cough, and constipation. The approval of amivantamab was the first approval of a targeted therapy for patients with advanced NSCLC harboring EGFR exon 20 insertion mutations.