Real-World Survival Outcomes With PARP Inhibitor Maintenance in Advanced Ovarian Cancer
Based on results from clinical trials demonstrating the ability of Poly(ADP-ribose) polymerase inhibitors (PARPis) to extend progression-free survival (PFS) and the time between chemotherapy and relapse, the National Comprehensive Cancer Network recommended PARPis following response to second-line (2L) chemotherapy as 2L maintenance treatment for patients with ovarian cancer. At the 2022 ASCO Annual meeting, Robert Lawrence Reid, MD, US Oncology, Medical Oncology, Virginia Cancer Specialists, Fairfax, VA, and colleagues presented estimates of real-world PFS and overall survival (OS) for patients on 2L PARPi maintenance therapy vs active surveillance.
The researchers used the iKnowMed electronic health record database and reviewed of patient charts within the US Oncology Network. Adult females were included in the data if they were diagnosed with advanced OC, had received a 2L platinum-containing regimen for advanced OC, and had ≥2 visits within the database between January 1, 2016 and December 1, 2020. Among these, a subset of charts were reviewed to confirm eligibility and to assess PFS. Patients were followed longitudinally until 31 March 2021, the last patient record, or date of death, whichever occurred earliest. Kaplan-Meier survival methods and log-rank tests were used to estimate and compare the OS as well as PFS of the groups to 24 months.
A total of 1154 patient met study inclusion criteria for advanced OC and either a PARPi or active surveillance for the 2L maintenance period. Of these, 142 patient charts were manually reviewed to assess real-world PFS: 84 received a PARPi, and 58 received active surveillance. Median age at the start of 2L maintenance was 65.7 years and was not significantly different between groups. There was a significant difference in the distribution of the ECOG PS category between groups (ECOG PS 0: 22.6% vs 1.7%, ECOG PS 1: 39.3% vs 50.0%, for PARPi vs active surveillance, respectively; P<.001). Median follow-up time from discontinuation of 2L platinum chemotherapy until the end of observation was significantly longer in the active surveillance group (41.5 vs 23.5 months; P< .001). PFS probability from the beginning of 2L maintenance was higher in the PARPi group vs active surveillance (24% vs 10% at 24 months; P= .0003). OS probability was also significantly higher in the PARPi group vs active surveillance (78% vs 55% at 24 months; P=.0272).
“This study of PARPi therapy vs active surveillance confirms the efficacy benefits that have been demonstrated in randomized clinical trials of PARPis vs placebo, and it provides further evidence of the real-world effectiveness of PARPi maintenance therapy to improve survival in a population with advanced OC,” wrote Dr Reid and colleagues.
Source:
Reid RL, et al. Real-world progression-free and overall survival for patients with advanced ovarian cancer utilizing PARP inhibitor second-line maintenance therapy vs active surveillance.Abstract presented at: ASCO Annual Meeting; June 3-7, 2022; Chicago, IL, and virtual. Abstract e18812.
