FDA to decide on zipalertinib for EGFR exon 20 NSCLC by Feb. 27, 2027
The NDA rests on a 35% response rate in 176 pretreated patients from the REZILIENT1 trial, in a field where no exon-20-targeted therapy has yet cleared amivantamab-based regimens as the benchmark to beat.
Executive Summary
- A regulatory decision, not a data readout, is now the pending catalyst: the underlying trial already reported a positive result, and review timing and label scope are what remain open.
- The application rests on a monotherapy response rate in previously treated patients that met its prespecified bar, giving the FDA a completed, already-public efficacy package to review rather than data still in progress.
- Several EGFR-directed programs, spanning antibody-drug conjugates, bispecifics, and other small molecules, are advancing in the same NSCLC population, so how the agency handles this application will shape the field's next comparator conversations.
- A Breakthrough Therapy Designation dating to 2021 reflects years of FDA engagement with the program ahead of this filing, a different footing than an application entering review cold.
The catalyst
Taiho Oncology, Taiho Pharmaceutical, and Cullinan Therapeutics announced on April 28, 2026 that the FDA accepted the NDA for zipalertinib for patients with locally advanced or metastatic NSCLC harboring EGFR exon 20 insertion mutations whose disease progressed on platinum-based chemotherapy, with or without amivantamab. The agency assigned a PDUFA target action date of February 27, 2027. The application is supported by the Phase 2b portion of the REZILIENT1 trial, registered as NCT04036682, which studies zipalertinib monotherapy in NSCLC patients with EGFR ex20ins mutations who received prior therapy. U.S+1U.S. Food and Drug Administration Accepts New Drug Application for Zipalertinib for the Treatment of Locally Advanced or Metastatic Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion MutationsApr 28, 2026A Phase 1/2 Trial of CLN-081 in Patients With Non-Small Cell Lung CancerNCT04036682
What REZILIENT1 showed
The trial met its primary endpoint of objective response rate, reporting a 35% ORR in the primary efficacy population of 176 patients, and the sponsors said zipalertinib "demonstrated clinically meaningful efficacy in the primary efficacy population (n=176), including 51 patients who had received" prior EGFR ex20ins-targeted therapy. Results were presented at the 2025 ASCO Annual Meeting and published simultaneously in the Journal of Clinical Oncology. Harold Keer, Chief Medical Officer of Taiho Oncology, called the NDA acceptance "an important milestone for this program" as the companies now work through FDA review. Zipalertinib carries a Breakthrough Therapy Designation the companies trace to January 2022, when Cullinan (then Cullinan Oncology) first disclosed the designation for CLN-081, the trial's original name for the compound. U.SU.S. Food and Drug Administration Accepts New Drug Application for Zipalertinib for the Treatment of Locally Advanced or Metastatic Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion MutationsApr 28, 2026
Trial operations behind the filing
NCT04036682 is Active, not recruiting, and enrollment grew from an original target of 80 to 284 patients over the trial's life, a scale-up recorded in October 2022 alongside a primary completion date extension from March 2023 to December 2023. The registry's primary completion date has moved seven times since the trial started in October 2019, most recently landing at October 13, 2025 in a June 2026 update. That amendment pattern reflects a trial that expanded its enrollment target and pushed completion dates across several years while running the additional cohorts, including the food-effect and combination modules, that ultimately built the efficacy package now under FDA review. NCT04036682A Phase 1/2 Trial of CLN-081 in Patients With Non-Small Cell Lung CancerNCT04036682
The competitive field
EGFR exon 20 insertion NSCLC is not an empty field: six direct comparators sharing the EGFR target are advancing in NSCLC, including AbbVie's telisotuzumab adizutecan, Regeneron's ubamatamab, and two Sichuan Baili programs (BL-B01D1 and izalontamab brengitecan), spanning antibody-drug conjugate, bispecific, and small-molecule modalities. Amivantamab, named explicitly in zipalertinib's own indication scope as a therapy patients may have already received, anchors the current standard after platinum chemotherapy. Zipalertinib's own portfolio includes a Phase 3 adjuvant trial (NCT07128199) and a Phase 3 safety-focused study (NCT05973773) nearing an October 2026 completion, indicating Taiho is already building beyond this first-line-after-progression indication toward earlier treatment settings. U.SU.S. Food and Drug Administration Accepts New Drug Application for Zipalertinib for the Treatment of Locally Advanced or Metastatic Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion MutationsApr 28, 2026
This analysis was produced using AI-assisted reporting systems, AppliedXL data, and official public records. These systems undergo editorial review, quality checks, and regular audits by human experts. Errors may still occur, as with any automated system. Always consult the linked primary sources. Read our AI Editorial Policy.