The study schema is shown below.
The objective response rate, now assessed by a BICR, showed an objective response rate of 17.9% and disease control rate of 51.3% at 19.9 months median follow-up. 92.3% percent of patients had some reduction in target lesion size reduction, with 35.9% of patients experiencing at least a partial response.
Radiographic progression-free survival in the updated cohort was 8.3 months, and the median overall survival was 20.4 months. Two patients died of pneumonitis that was attributed to treatment. The most common grade 3 and 4 adverse events were febrile neutropenia (12 patients) and anemia (5 patients).
This updated data confirms prior presented data suggesting clinical activity of the combination of docetaxel plus pembrolizumab in patients who had progressed on anti-androgen therapy with either enzalutamide or abiraterone. Results are awaited from the randomized phase 3 study of docetaxel + prednisone versus docetaxel + prednisone + pembrolizumab (KEYNOTE-921, NCT03834506) in mCRPC patients treated with exactly one prior anti-androgen therapy.
Presented by: Emanuela Romano, MD, Medical Director of the Center for Cancer Immunotherapy, Institut Curie, Paris, France
Written by: Alok Tewari, MD, Ph.D., Medical Oncologist at the Dana-Farber Cancer Institute, at the 2020 European Society for Medical Oncology Virtual Congress (#ESMO20), September 19th-September 21st, 2020