Duration of treatment, treatment adherence, and treatment discontinuations associated with second-line PARP inhibitor or bevacizumab maintenance regimens for recurrent ovarian cancer (338)

Objectives: Maintenance therapy after response to platinum has been shown in clinical trials to prolong progression-free survival in patients with recurrent ovarian cancer. We sought to describe current practice patterns for patients receiving maintenance therapy for recurrent ovarian cancer from real-world usage. Methods: We conducted a retrospective cohort study of US patients >18 years old with recurrent ovarian cancer and commercial or medicare advantage claims data in the Optum Research Database. Patients were required to have at least two diagnoses of ovarian cancer between July 1, 2010, and December 31, 2019, subsequent systemic chemotherapy, and an index second-line maintenance therapy with a poly(ADP-ribose) polymerase (PARP) inhibitor or bevacizumab between January 1, 2017, and end of patient follow-up. Patients were followed until death, end of the study, or health plan disenrollment. Treatment duration and adherence were evaluated using descriptive statistics, and a Cox proportional hazards model was used to ascertain the time without dose interruption or discontinuation by the therapy group. Results: A total of 1092 patients met the inclusion criteria and had at least two lines of therapy. Among these, 446 (40.8%) subsequently received PARP inhibitor or bevacizumab maintenance treatment: 38 (8.5%) received rucaparib, 110 (24.7%) niraparib, 114 (25.6%) olaparib, and 184 (41.3%) bevacizumab. Average duration of maintenance treatment was as follows: olaparib, 187.6 (standard deviation [SD]: 178.7) days; bevacizumab, 185.2 (149.2) days; rucaparib, 147.2 (155.4) days; and niraparib, 124.2 (122.9) days. Treatment adherence was similar across all therapies (86-88%). Dose reduction was numerically more common during this time period in the niraparib group (28.2%) than rucaparib (21.1%) or olaparib (20.2%) groups, although the difference in frequency did not reach statistical significance. In a Cox proportional hazards model, niraparib was associated with a significantly shorter dose interruption or discontinuation time than rucaparib (HR: 3.7; p=0.03) (Figure). Olaparib and bevacizumab also had higher HRs for dose interruptions or discontinuations compared with rucaparib, but these estimates were not statistically significant (HR: 1.5; p=0.498 and HR: 1.4; p=0.584, respectively). Conclusions: Less than half of recurrent ovarian cancer patients received maintenance therapy with a PARP inhibitor or bevacizumab. For patients receiving maintenance therapy after a second chemotherapy regimen, while adherence was >86% in all regimens, dose modifications or discontinuation levels varied depending on the treatment received. Niraparib was associated with the shortest time to dose interruption or discontinuation among the agents evaluated. Objectives: Maintenance therapy after response to platinum has been shown in clinical trials to prolong progression-free survival in patients with recurrent ovarian cancer. We sought to describe current practice patterns for patients receiving maintenance therapy for recurrent ovarian cancer from real-world usage. Methods: We conducted a retrospective cohort study of US patients >18 years old with recurrent ovarian cancer and commercial or medicare advantage claims data in the Optum Research Database. Patients were required to have at least two diagnoses of ovarian cancer between July 1, 2010, and December 31, 2019, subsequent systemic chemotherapy, and an index second-line maintenance therapy with a poly(ADP-ribose) polymerase (PARP) inhibitor or bevacizumab between January 1, 2017, and end of patient follow-up. Patients were followed until death, end of the study, or health plan disenrollment. Treatment duration and adherence were evaluated using descriptive statistics, and a Cox proportional hazards model was used to ascertain the time without dose interruption or discontinuation by the therapy group. Results: A total of 1092 patients met the inclusion criteria and had at least two lines of therapy. Among these, 446 (40.8%) subsequently received PARP inhibitor or bevacizumab maintenance treatment: 38 (8.5%) received rucaparib, 110 (24.7%) niraparib, 114 (25.6%) olaparib, and 184 (41.3%) bevacizumab. Average duration of maintenance treatment was as follows: olaparib, 187.6 (standard deviation [SD]: 178.7) days; bevacizumab, 185.2 (149.2) days; rucaparib, 147.2 (155.4) days; and niraparib, 124.2 (122.9) days. Treatment adherence was similar across all therapies (86-88%). Dose reduction was numerically more common during this time period in the niraparib group (28.2%) than rucaparib (21.1%) or olaparib (20.2%) groups, although the difference in frequency did not reach statistical significance. In a Cox proportional hazards model, niraparib was associated with a significantly shorter dose interruption or discontinuation time than rucaparib (HR: 3.7; p=0.03) (Figure). Olaparib and bevacizumab also had higher HRs for dose interruptions or discontinuations compared with rucaparib, but these estimates were not statistically significant (HR: 1.5; p=0.498 and HR: 1.4; p=0.584, respectively). Conclusions: Less than half of recurrent ovarian cancer patients received maintenance therapy with a PARP inhibitor or bevacizumab. For patients receiving maintenance therapy after a second chemotherapy regimen, while adherence was >86% in all regimens, dose modifications or discontinuation levels varied depending on the treatment received. Niraparib was associated with the shortest time to dose interruption or discontinuation among the agents evaluated.