Taiho Oncology and Cullinan Therapeutics said their Phase 3 trial of zipalertinib, a next-generation EGFR inhibitor, was stopped early at a planned interim analysis in front-line lung cancer with EGFR exon 20 insertion mutations. The partners reported that the oral drug plus chemotherapy met a pre-specified threshold for progression-free survival, triggering the unblinding. The update sets up a fresh regulatory timeline for the program. The FDA is already reviewing zipalertinib as a second-line treatment, with a decision expected by late February, while the new Phase 3 momentum could support an expanded label if the data hold across endpoints. The result intensifies competition in EGFR exon 20 insertion disease, where incumbents and other upcoming targeted options continue to battle for positioning in earlier lines. Taiho and Cullinan previously reported Phase 2 tumor shrinkage rates exceeding one-third of patients, supporting the rationale for moving quickly into Phase 3.