SOLO-1’s invited discussant, Jonathan Ledermann, MD, Professor of Medical Oncology at UCL Cancer Institute and University College London Hospitals, predicted that “an overall survival benefit will occur” with maintenance olaparib, based on the study’s long follow-up and encouraging results from key secondary endpoints. Analysis of progression-free survival with longer follow-up and as the secondary endpoints provide more mature results, although overall survival is the outcome ultimately desired from clinical trials, he said.

With longer follow-up, median progression-free survival was 56.0 months with olaparib (and not reached in the primary analysis); with placebo, it remained 13.8 months at both time points. At 60 months, 48% of olaparib-treated patients were free of recurrence vs 21% of those not receiving maintenance therapy.

‘Interesting Observation’

“An interesting observation is the slow change we have seen in the olaparib arm. Only 118 events have occurred. There were 102 events in the initial analysis. This is telling us that something is happening way beyond the stopping of olaparib at 24 months,” Dr. Ledermann said.

“Overall survival data will help disentangle further the benefits of first-line vs second-line use of PARP inhibitors, particularly in the population of patients with BRCA mutations or wild-type BRCA and homologous repair deficiency,” he noted. “These are interesting data reshaping the treatment of ovarian cancer and providing hitherto-unseen benefits.” 

DISCLOSURE: Dr. Ledermann has received honoraria from AstraZeneca/MedImmune; has served as a consultant or advisor to Artios, AstraZeneca/MedImmune, Clovis Oncology, Cristal Therapeutics, Eisai, Merck, Pfizer, Seattle Genetics, and Tesaro; has participated in a speakers bureau for Clovis Oncology, Pfizer, and Tesaro/GSK; has received institutional research funding from AstraZeneca and MSD Oncology; has been reimbursed for travel, accommodations, or other expenses by Clovis; and has held other relationships with Regeneron.