ASCO20: Cabozantinib Plus Atezolizumab for Castration-Resistant Prostate Cancer
Posted: Tuesday, June 16, 2020
In a trial studying the combination therapy of cabozantinib and atezolizumab, men with metastatic castration-resistant prostate cancer had durable responses and a tolerable safety profile. In fact, further study of this combination in men with high-risk disease is being pursued. This work was presented by Neeraj Agarwal, MD, of the University of Utah, Salt Lake City, during the ASCO20 Virtual Scientific Program (Abstract 5564).
This cohort of the COSMIC-021 trial enrolled 44 men with prostate cancer who had radiographic disease progression in soft tissue after treatment with enzalutamide and/or abiraterone. Patients were administered 40 mg of oral cabozantinib once a day plus 1,200 mg of atezolizumab intravenously every 3 weeks. Patients underwent imaging studies every 6 weeks for the first year followed by every 12 weeks thereafter.
As of December 2019, the median follow-up was 12.6 months, and the median duration of treatment was 6.3 months. The overall response rate was 32%, with 2 patients experiencing a complete response; 12, a partial response; and 21, stable disease. The disease control rate was 80% among all patients. Of the 36 patients with high-risk disease (visceral and/or extrapelvic lymph node metastases), the overall response rate was 33%, according to the Response Evaluation Criteria in Solid Tumors (RECIST), v1.1. The median duration of response in all responding patients according to RECIST v1.1 was 8.3 months.
There were 34 patients who underwent post-baseline prostate-specific antigen (PSA) evaluation. Of them, 17 patients (50%) had a decrease in PSA level. In addition, of the 12 responders who underwent PSA evaluation, 8 (67%) had PSA levels fall by more than 50%.
Common treatment-related adverse events of any grade were fatigue (50%), nausea (43%), decreased appetite (39%), diarrhea (39%), dysgeusia (34%), and plantar-palmar erythrodysthesia (32%). One of the patients, who was 90 years old, experienced grade 5 dehydration.
Disclosures: For full authors’ disclosures, visit coi.asco.org.
