Real-world outcomes associated with use of front-line bevacizumab in ovarian cancer

In the pivotal ICON7 study, addition of bevacizumab to front-line treatment of ovarian cancer (OC) significantly improved overall survival (OS) (p = 0.03) in a high-risk subgroup of patients with suboptimally debulked/unresectable stage III or IV disease, leading to approval in Ontario, Canada in March 2016. Here we describe utilization of bevacizumab for front-line, high-risk OC and determine outcomes in routine clinical practice.

Provincial administrative databases were utilized to identify all patients treated with front-line bevacizumab following its approval. Median OS (mOS) was determined using the Kaplan-Meier method. Factors associated with OS were identified using a Cox proportional hazard model. A comparative effectiveness analysis was performed to determine mOS pre- (2006-2016) and post- (2016-2019) approval.

From March 2016 to October 2019, 282 patients received bevacizumab. Mean age was 64 years old, and 58% had stage IV disease. Median survival was 29 months and was longer in stage III (37 months) compared to stage IV disease (28 months). In a comparative effectiveness analysis of patients with stage IV serous OC, post-approval uptake of bevacizumab was low (23%). Median OS was similar pre (26 months) and post (27 months) approval (HR 0.92, 0.75-1.12, p = 0.383).

Survival in real-world patients treated with front-line bevacizumab is shorter than in pivotal clinical trials. Survival in stage IV serous patients has not significantly improved post public reimbursement of bevacizumab. This analysis was limited by poor uptake, however mOS was similar in patients who did and did not receive bevacizumab.