Trial results for the KEYNOTE-867 study (NCT03924869) investigating pembrolizumab (Keytruda) with stereotactic body radiotherapy (SBRT) in adults with unresected Stage I or II non-small cell lung cancer (NSCLC) were posted on ClinicalTrials.gov on 2025-05-11. The study reported a median Event-free Survival (EFS) of 31.2 months for the pembrolizumab arm compared to 28.3 months for the placebo arm.
Background
The KEYNOTE-867 study, also known as "Efficacy and Safety Study of Stereotactic Body Radiotherapy (SBRT) With or Without Pembrolizumab (MK-3475) in Adults With Unresected Stage I or II Non-Small Cell Lung Cancer (NSCLC) (MK-3475-867/KEYNOTE-867)," investigated the addition of pembrolizumab to SBRT for the treatment of unresected Stage I or II non-small cell lung cancer. The primary hypothesis was that SBRT plus pembrolizumab would prolong Event-free Survival (EFS) compared to SBRT plus placebo.
Trial design
The KEYNOTE-867 study (NCT03924869) was a Phase 3, randomized trial that enrolled 448 participants. The study focused on adults with unresected Stage I or II Non-Small Cell Lung Cancer. Participants were assigned to receive either SBRT plus pembrolizumab or SBRT plus placebo. The trial's overall status is TERMINATED.
Key results
The trial evaluated several key outcomes:
- Event-free Survival (EFS): The median EFS was 31.2 months for the SBRT + Pembrolizumab group and 28.3 months for the SBRT + Placebo group. The Hazard Ratio (HR) for EFS was 0.92 (95% Confidence Interval: 0.69 to 1.24) with a p-value of 0.2932.
- Overall Survival (OS): The median OS was 54.7 months for the SBRT + Pembrolizumab group. The median OS for the SBRT + Placebo group was NA months. The Hazard Ratio (HR) for OS was 1.33 (95% Confidence Interval: 0.93 to 1.9) with a p-value of 0.93971.
- Time to Death or Distant Metastases (TDDM): The median TDDM was 39.1 months for the SBRT + Pembrolizumab group and 41.3 months for the SBRT + Placebo group. The Hazard Ratio (HR) for TDDM was 1.02 (95% Confidence Interval: 0.74 to 1.42).
- Adverse Events (AE): A total of 217 participants in the SBRT + Pembrolizumab group experienced an AE, compared to 200 in the SBRT + Placebo group. 62 participants in the SBRT + Pembrolizumab group discontinued study treatment due to an AE, versus 25 in the SBRT + Placebo group.
- Quality of Life (EORTC QLQ-C30 Global Health Status/Quality of Life): The Least Squares Mean change from baseline was -2.17 for the SBRT + Pembrolizumab group and -0.96 for the SBRT + Placebo group. The Mean Difference (Final Values) was -1.21 (95% Confidence Interval: -4.9 to 2.48) with a p-value of 0.5187.
What this means
The results of the KEYNOTE-867 trial indicate that the addition of pembrolizumab to SBRT did not demonstrate a statistically significant improvement in Event-free Survival for adults with unresected Stage I or II NSCLC, despite a numerically higher median EFS in the pembrolizumab arm. The p-value of 0.2932 for EFS suggests no significant difference between the treatment arms. Overall Survival data for the placebo arm was not available. The pembrolizumab arm also showed a higher number of participants experiencing adverse events and discontinuing treatment due to adverse events. No significant difference was observed in the quality of life assessment between the two groups.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03924869, titled "Efficacy and Safety Study of Stereotactic Body Radiotherapy (SBRT) With or Without Pembrolizumab (MK-3475) in Adults With Unresected Stage I or II Non-Small Cell Lung Cancer (NSCLC) (MK-3475-867/KEYNOTE-867)," were posted on 2025-05-11 on clinicaltrials.gov.