Pivotal KEYNOTE-671 trial meets dual primary endpoint of overall survival (OS) in resectable stage II, IIIA or IIIB non-small cell lung cancer

At a pre-specified interim analysis, Keytruda plus chemotherapy before surgery (neoadjuvant), followed by resection and Keytruda as a single agent after surgery (adjuvant), demonstrated a statistically significant and clinically meaningful improvement in OS compared to neoadjuvant placebo plus chemotherapy followed by adjuvant placebo in these patients.

The safety profile of Keytruda was consistent with that observed in previously reported studies; no new safety signals were identified. Full results from this analysis of KEYNOTE-671 will be presented at the European Society for Medical Oncology (ESMO) Congress 2023 and shared with regulatory authorities worldwide.

“This is a significant milestone in the treatment of resectable non-small cell lung cancer, as it represents the first Phase III study to show a statistically significant overall survival benefit for these patients with stage II, IIIA or IIIB (T3-4N2) non-small cell lung cancer. These results build upon the previously reported event-free survival data, and demonstrate the potential for this Keytruda based regimen to help extend the lives of these patients,” said Dr. Marjorie Green, senior vice president and head of late-stage oncology, global clinical development, Merck Research Laboratories.

As previously announced, at the first interim analysis, KEYNOTE-671 met the other one of its dual primary endpoints, event-free survival (EFS), as well as its key secondary endpoints of pathological complete response (pCR) and major pathological response (mPR). These results were presented at the 2023 American Society of Clinical Oncology (ASCO) and, based on these data, the FDA has accepted Merck’s new supplemental Biologics License Application (sBLA) with a Prescription Drug User Fee Act (PDUFA), or target action, date of October 16, 2023.

KEYNOTE-671 is a randomized, double-blind Phase 3 trial (ClinicalTrials.gov, NCT03425643) evaluating neoadjuvant Keytruda plus chemotherapy, followed by adjuvant Keytruda as a single agent versus placebo plus neoadjuvant chemotherapy, followed by adjuvant placebo in patients with resectable stage II, IIIA or IIIB (T3-4N2) NSCLC. The trial’s dual primary endpoints are EFS and OS. Key secondary endpoints include pCR and mPR. The study enrolled 786 patients who were randomly assigned (1:1) to receive either: Keytruda (200 mg intravenously [IV] every three weeks [Q3W] for up to four cycles) plus chemotherapy (cisplatin [75 mg/m^2, IV; given on Day 1 of each cycle] and either gemcitabine [1000 mg/m^2, IV; given on Days 1 and 8 of each cycle) or pemetrexed [500 mg/m^2, IV; given on Day 1 of each cycle]) as neoadjuvant therapy prior to surgery, followed by Keytruda (200 mg IV Q3W for up to 13 cycles) as adjuvant therapy post-surgery, or Placebo (saline IV Q3W for up to four cycles) plus chemotherapy (cisplatin [75 mg/m^2, IV; given on Day 1 of each cycle] and either gemcitabine [1000 mg/m^2, IV; given on Days 1 and 8 of each cycle] or pemetrexed [500 mg/m^2, IV; given on Day 1 of each cycle]) as neoadjuvant therapy prior to surgery, followed by placebo (saline IV Q3W for up to 13 cycles) as adjuvant therapy post-surgery.