Key Clinical Takeaways: 

• In the phase 3 KEYNOTE-937 trial, adjuvant pembrolizumab did not significantly improve recurrence-free survival compared with placebo following curative-intent resection or local ablation for hepatocellular carcinoma.
• No differences were observed between treatment arms in overall survival, distant metastases–free survival, or time to recurrence at a median follow-up of more than 4 years.
• Pembrolizumab was associated with higher rates of grade ≥3 and drug-related adverse events, with no treatment-related deaths reported.

Stephen Lam Chan, MD, Hong Kong Cancer Institute, Hong Kong, China, discusses results from the phase 3 KEYNOTE-937 trial evaluating pembrolizumab versus placebo as adjuvant therapy following surgical resection or local ablation in patients with hepatocellular carcinoma. 

At the third interim analysis, adjuvant pembrolizumab did not improve recurrence-free survival, and no benefit was observed for overall survival or distant metastases-free survival.

This study was presented at the 2026 American Society of Clinical Oncology (ASCO) Gastrointestinal Cancers Symposium in San Francisco, California.

Transcript:

Hello everyone, I’m Dr Stephen Chan from the department of clinical oncology at the Chinese University of Hong Kong in Hong Kong. On behalf of all the investigators, it’s my pleasure to give you a very brief overview of the results of the KEYNOTE-937 study, which is titled adjuvant pembrolizumab for participants with hepatocellular carcinoma (HCC) who have received surgery or local ablation.

We know that there is a huge unmet need to develop adjuvant therapy for HCC patients to reduce the chance of recurrence and also, hopefully, improve overall survival following curative-intent treatment, either surgery or local ablation. In this study, 959 patients were randomized in a 1:1 ratio to receive 1 year of pembrolizumab at 200 mg every 3 weeks versus placebo. All patients were treated until disease recurrence, unacceptable toxicity, intercurrent illness, or withdrawal. There were 2 primary end points, recurrence-free survival and overall survival. 

Regarding the key results presented at ASCO GI this month, for recurrence-free survival, the median value for the pembrolizumab arm was 46.7 months, while the median recurrence-free survival for the placebo arm was 45.5 months. The hazard ratio was 1.06, and the P value was 0.719. In summary, there was no statistically significant difference between pembrolizumab and placebo. Regarding overall survival, the data were not mature enough for formal statistical analysis, but based on the descriptive hazard ratio, it was 1.08. Again, there was no, or it is unlikely that there will be, a difference between the pembrolizumab and placebo arms. 

In summary, this study did not demonstrate an improvement in recurrence-free survival versus placebo in the study population. The study did not proceed to final analysis because the recurrence-free survival hypothesis was not met; hence, overall survival was not tested statistically. We did not observe any new safety signals. 

I think the important point is that there is no role for adjuvant pembrolizumab after surgery or ablation for HCC, and we need to study new regimens for this population in the adjuvant setting.

Source: 

Chan SL, Bouattour M, Yau T, et al. Adjuvant pembrolizumab for participants with hepatocellular carcinoma and complete radiologic response after surgical resection or local ablation: The phase 3 KEYNOTE-937 study. Presented at ASCO Gastrointestinal Cancers Symposium. January 8 - 12, 2026; San Francisco, California. Abstract 477.