ASCO 2018: Dr. Westin Sheds Light on PARP Inhibitor Abstracts in Ovarian Cancer

Shannon N. Westin, MD, associate professor in the Department of Gynecologic Oncology and Reproductive Medicine, Division of Surgery, at The University of Texas MD Anderson Cancer Center, discusses data from the TOPACIO/KEYNOTE-162 and QUADRA studies presented at the 2018 ASCO Annual Meeting.

The TOPACIO/KEYNOTE-162 trial explored the combination of niraparib (Zejula) and pembrolizumab (Keytruda) in cohorts of patients with ovarian cancer and triple-negative breast cancer. Updated data presented at the meeting show that the regimen is synergistic and that there is activity in the BRCA wild-type ovarian cancer population, which is unique, Westin explains. That is exciting because it demonstrates a method to overcome some sort of resistance, she adds.

Results of the phase II QUADRA trial evaluated niraparib in a heavily pretreated patient population with relapsed ovarian cancer, with response rates ranging between 60% and 70% in a BRCA-mutant ovarian cancer population, but there were also activity shown in the BRCA wild-type patients, she adds. Researchers are just "scratching the surface" in determining which patients are most likely to benefit from PARP inhibition, she says.

A focus of ovarian cancer trials of this year's meeting was on refining precision medicine, Westin concluded, which can be highlighted in clinical trials such as GOG-0213. This was a phase III randomized trial of secondary surgical cytoreduction followed by platinum-based combination chemotherapy with or without bevacizumab in platinum-sensitive, recurrent ovarian cancer.