Roy Baynes, MD, PhD
Pembrolizumab (Keytruda) did not improve survival as a second-line treatment for PD-L1–positive patients with advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma, according to findings from the phase III KEYNOTE-061 trial.
Among 7 patients with microsatellite instability-high (MSI-H) tumors, the ORR with pembrolizumab was 57.1% and the CR rate was 14.3%. The disease control rate was 71.4%. In those with non–MSI-H tumors (n = 167), the ORR was 9% and the CR rate was 2.4%. The disease control rate was 22.2%.
The most frequently occurring treatment-related adverse events (AEs) of all grades were fatigue (18.9%), pruritus (8.9%), rash (8.5%), hypothyroidism (7.7%), decreased appetite (7.3%), anemia (6.9%), nausea (6.9%), diarrhea (6.6%), and arthralgia (5.8%). There were 2 treatment-related grade 5 AEs (acute kidney injury and pleural effusion).
The accelerated approval of pembrolizumab for this indication is contingent on the results of a confirmatory trial. The ongoing phase III KEYNOTE-062 trial is evaluating pembrolizumab alone and in combination with chemotherapy in the frontline setting for PD-L1–positive advanced gastric or GEJ cancer, and the phase III KEYNOTE-585 trial is studying the combination of pembrolizumab and chemotherapy in the neoadjuvant and adjuvant settings.
- FDA Approves Merck’s KEYTRUDA® (pembrolizumab) for Previously Treated Patients with Recurrent Locally Advanced or Metastatic Gastric or Gastroesophageal Junction Cancer Whose Tumors Express PD-L1 (CPS Greater Than or Equal to 1). Merck. http://bit.ly/2wberGs. Accessed September 22, 2017.
- Fuchs CS, Doi T, Jang RW-J, et al. KEYNOTE-059 cohort 1: Efficacy and safety of pembrolizumab (pembro) monotherapy in patients with previously treated advanced gastric cancer. J Clin Oncol. 2017;35 (suppl; abstr 4003).