Cost-effectiveness of olaparib plus bevacizumab versus bevacizumab monotherapy in the maintenance of patients with homologous recombination deficiency-positive advanced ovarian cancer after response to first-line platinum-based chemotherapy

Abstract

ObjectiveThe PAOLA-1 trial confirmed that adding olaparib to bevacizumab significantly increased clinical benefit following response to platinum-based chemotherapy in homologous recombination deficiency-positive ovarian cancer. The objective of this analysis was to determine the cost-effectiveness of olaparib plus bevacizumab compared with bevacizumab alone as maintenance treatment for patients with homologous recombination deficiency-positive advanced ovarian cancer from the Spanish National Health System perspective.MethodsA lifetime partitioned survival model with four health states (progression-free, post-progression 1, post-progression 2, and death) and monthly cycles was developed. Long-term survival, defined as 60 months, was included as a landmark to extrapolate progression-free survival from PAOLA-1. Weibull distribution was selected as the most accurate survival model for progression-free survival extrapolation. Time to second progression and overall survival were extrapolated using parametric survival models. Mortality was obtained from the overall survival and adjusted by Spanish women mortality rates. Health state utilities and utility decrements for adverse events were included. An expert panel validated data and assumptions. Direct costs (in 2021 euros (€)) were obtained from local sources and included drug acquisition and administration, subsequent therapies, monitoring costs, adverse events, and palliative care. A 3% annual discount rate was applied to costs and outcomes. The incremental cost-effectiveness ratio was calculated as cost per quality-adjusted life-years (QALYs) gained. Deterministic and probabilistic sensitivity analyses were performed.ResultsCompared with bevacizumab alone, olaparib plus bevacizumab increased QALYs and life-years by 2.39 and 2.77, respectively, at an incremental cost of €58 295.31, resulting in an incremental cost-effectiveness ratio of €24 371/QALY. Probabilistic sensitivity analysis demonstrated that olaparib plus bevacizumab had a 49.5% and 90.3% probability of being cost-effective versus bevacizumab alone at a willingness-to-pay threshold of €25 000 and €60 000 per QALY gained, respectively.ConclusionFor patients with homologous recombination deficiency-positive advanced ovarian cancer, olaparib plus bevacizumab is a cost-effective maintenance therapy compared with bevacizumab alone in Spain.