Median follow-up in Cohort A at the time of the current analysis was 16.7 months, and in Cohort B, the median follow-up was 17.3 months. Treatment was ongoing in 15 and 6 patients in the cohorts, respectively. Reasons for discontinuation included radiographic progression (204 and 62 patients), clinical progression (24 and 17 patients), adverse events (22 and 3 patients), and patient withdrawal (9 and 3 patients). Complete responses occurred in 1 and 0 patients in the groups, respectively.
Median progression-free survival in both cohorts was 2.1 months, and overall survival was not reached in Cohort A, while it was 17.6 months in the more heavily pretreated Cohort B.
“Recurrent ovarian cancer is the leading cause of death from gynecologic cancer. The majority of our patients relapse after first-line platinum and taxane-based chemotherapy, and the degree of platinum sensitivity will predict the tumor response rates with platinum, as well as survival time,” she said, noting that subsequent recurrences become increasingly platinum and treatment resistant.
Current treatment options in these patients include chemotherapy with or without bevacizumab; the ORRs with single-agent immune checkpoint blockade are about 10%, but in KEYNOTE-028, patients with PD-L1–positive advanced recurrent ovarian cancer had an ORR of 11.5% with pembrolizumab treatment, she said.