Pembrolizumab in Combination Therapy for Resistant Multiple Myeloma
Posted: Monday, August 6, 2018
The benefit-risk profile for adding pembrolizumab to a regimen containing pomalidomide and dexamethasone seems to be unfavorable for the treatment of relapsed or refractory multiple myeloma. These findings from the phase III KEYNOTE-183 trial were presented by Maria-Victoria Mateos, MD, PhD, of the University Hospital of Salamanca, Spain, and colleagues, at the 2018 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 8021).
In the study, 249 patients were randomized 1:1 to receive either pembrolizumab in combination with pomalidomide and low-dose dexamethasone (n = 125) or pomalidomide and dexamethasone alone (n = 124). Based on the interim data, the U.S. Food and Drug Administration halted the study in July 2017. However, evaluation of T-cell subsets and cytokines, along with long-term safety and survival follow-up, is ongoing.
After a median follow-up of 7.8 months and 8.6 months in the pembrolizumab and pomalidomide/dexamethasone arms, respectively, the median progression-free survival was 5.6 months versus 8.4 months. The median time to disease was 8.1 months with pembrolizumab and 8.7 months without it.
Adverse events with ≥ 5% difference in the pembrolizumab arm included neutropenia (38% vs. 27%), nausea (17% vs. 12%), pneumonia (23% vs. 15%), alanine aminotransferase level increase (10% vs. 3%), and headache (13% vs. 4%). Additionally, 18% of patients who received pembrolizumab experienced immune-mediated adverse events, and 23% of patients in that arm died, versus 17% in the pomalidomide/dexamethasone arm.
