FDA OKs Bispecific Antibody for Rare Lung Cancer Subtype

The FDA approved amivantamab-vmjw (Rybrevant) on Friday as the first treatment for patients with non-small cell lung cancer (NSCLC) harboring EGFR exon 20 insertion mutations.

Amivantamab is a bispecific antibody that targets EGFR and mesenchymal-epithelial transition factor pathways. EGFR exon 20 insertion mutations occur in approximately 2% to 3% of NSCLC patients, and are associated with rapid cell growth.

“Advances in precision oncology continue to facilitate drug development, allowing diseases like lung cancer to be subset into biomarker-defined populations appropriate for targeted therapies,” said Julia Beaver, MD, chief of medical oncology in the FDA’s Oncology Center of Excellence, in a statement. “With today’s approval, for the first time, patients with non-small cell lung cancer with EGFR exon 20 insertion mutations will have a targeted treatment option.”

Approval was based on results from the phase I CHRYSALIS trial, a multicenter non-randomized, open-label, multicohort study that included 81 patients with NSCLC and EGFR exon 20 insertion mutations who received amivantamab on or after progressing after platinum-based chemotherapy. Patients received amivantamab once weekly for 4 weeks, and then every 2 weeks until disease progression or unacceptable toxicity.

The overall response rate in the trial population was 40% (95% CI 29%-51%). Median duration of response was 11.1 months (95% CI 6.9-not evaluable), with nearly two-thirds of patients having a duration of response of at least 6 months.

The most common side effects associated with the drug were rash, infusion-related reactions, paronychia, musculoskeletal pain, dyspnea, nausea, fatigue, edema, stomatitis, cough, constipation, and vomiting.

“Lung cancer is a complex disease, and through the study and deeper understanding of genetic alterations like EGFR exon 20 insertion mutations, we are able to target the disease in new ways and improve treatment outcomes for patients,” investigator Joshua Sabari, MD, of NYU Langone Health Perlmutter Cancer Center in New York City, said in a news release from drugmaker Janssen.

Amivantamab “brings an important new therapeutic approach to physicians caring for patients with this serious and rare type of lung cancer,” Sabari added.

Along with the approval, the FDA also approved the Guardant360 CDx as a companion diagnostic for the drug.