Re-treatment with PARPi in patients with recurrent epithelial ovarian cancer: A single institutional experience

We aimed to evaluate real-life experiences with the re-challenge of poly(ADP-Ribose)Polymerase (PARP) inhibitors (PARPi) after a prior PARPi therapy in patients with recurrent EOC.

A retrospective descriptive study was conducted at a tertiary care center of excellence for ovarian cancer. Demographic, pathological, and therapeutic data were collected for patients with recurrent epithelial ovarian cancer who were re-treated with PARPi in their therapy course.

Twenty-nine patients were included in the study. Twenty-six patients received the second PARPi as maintenance therapy after two different lines of therapy and three patients received the second PARPi as upfront therapy after progression. Most of the patients (57.7%) were exposed to first PARPi after a second-line therapy. The median progression-free survival under the first and second PARPi therapy was estimated at 15 and 7 months respectively. PFS under the second PARPi after platinum-based chemotherapy was better after a complete remission with a median PFS of 8.5 months, compared to patients with partial remission (5.5 months). A better PFS was noted in case of negative BRCA status under the second PARPi therapy (median PFS of 7.4 vs. 4.5 months, p = 0.11). The second PARPi therapy was mainly discontinued due to disease progression (84.6% of the cases). Discontinuation of treatment with the second PARP due to toxicity was needed in one case who developed a myelodysplastic syndrome.

Real-life data support prospective evidence that patients with recurrent EOC may derive benefit of the re-treatment with PARPi in case of clear response to the last platinum-based therapy.