Efficacy of Perioperative Pembrolizumab/Chemotherapy in Early NSCLC

Heather Wakelee, MD, from Stanford University School of Medicine and the Stanford Cancer Institute, discusses the efficacy findings from the phase 3 KEYNOTE-671 clinical trial (NCT03425643) evaluating the addition of pembrolizumab (Keytruda) to neoadjuvant platinum-based chemotherapy followed by resection and adjuvant pembrolizumab alone for patients with early-stage non–small cell lung cancer (NSCLC).

According to findings from the double-blind study presented at the 2023 ASCO Annual Meeting, at 24 months, the event-free survival rate was 62.4% with pembrolizumab plus chemotherapy and adjuvant pembrolizumab vs 40.6% for placebo plus chemotherapy (HR, 0.58; 95% CI, 0.46-0.72; P < .00001). Overall survival (OS) data were immature at the time of the analysis, and at 24 months, the OS rate was 80.9% in the pembrolizumab arm vs 77.6% in the placebo arm (HR, 0.73; 95% CI, 0.54-0.99; P = .02124).

Transcription:

0:10 | The KEYNOTE-671 trial had 2 primary dual end points, and the first is event-free survival and event-free survival is a little different from disease-free survival, which we talk about a lot. Disease-free survival is a time point you can only have when you have no known disease. Since the trials start before surgery events are also included in an event that would be something that prevented the patient from going to surgery. It's defined a little bit differently in all of the neoadjuvant and perioperative trials, but essentially, it is the same and that is important for people to know. So event-free survival or overall survival were both the primary end points and the first interim analysis, we actually had hit the event-free survival, which had a hazard ratio of .58, which was highly statistically significant.

1:00 | Now, the overall survival curves actually looked quite good with separation, but not enough events had occurred for that to be statistically significant, so we can't really call it at this first interim analysis, but that will continue to be followed. The study also looked at major pathological responses and complete pathological responses and in both of those, it was much better when you added the pembrolizumab vs on the placebo arms. Those numbers were keeping with what we've seen with other neoadjuvant and perioperative trials with checkpoint inhibitors and chemotherapy prior to surgery.