Study Background

This Phase 2/3 trial enrolls patients with metastatic non‑small cell lung cancer (NSCLC) harboring homozygous MTAP loss. MTAP deficiency is known to alter methyladenosine metabolism within tumors, increasing dependence on PRMT5. Navlimetostat is an MTA‑cooperative inhibitor that selectively targets PRMT5, and is expected to synergize with existing immunotherapies and chemotherapy.

Mechanism of Action

Navlimetostat, as a PRMT5 inhibitor, blocks the hyper‑activated PRMT5 in MTAP‑deficient tumors, thereby suppressing tumor proliferation and immune evasion concurrently. Pembrolizumab is a PD‑1 inhibitor that restores immune recognition of tumor cells, enhancing antitumor activity. The combination is anticipated to remodel the tumor microenvironment and improve therapeutic response.

Clinical Design and Objectives

The study is randomized, double‑blind, placebo‑controlled, with primary endpoints of progression‑free survival (PFS) and overall survival (OS). Eligible participants are treatment‑naïve patients with metastatic NSCLC, and MTAP loss is confirmed by tissue biopsy. The trial is projected to complete in 2029, and a positive efficacy signal at interim analysis could enable accelerated approval.

Market and Competitive Landscape

While first‑line NSCLC therapy currently standardizes the combination of immunotherapy and chemotherapy, no agents specifically target MTAP loss. Navlimetostat represents the first candidate addressing this unmet need; if successful, it could differentiate BMS’s portfolio and secure a proprietary position relative to competitors. Moreover, the PRMT5 inhibitor platform has potential applicability across other tumor types, offering long‑term value.