A cost‐effectiveness analysis of avelumab plus best supportive care versus best supportive care alone as first‐line maintenance treatment for patients with locally advanced or metastatic urothelial carcinoma in Taiwan

BACKGROUND: Patients with locally advanced or metastatic urothelial carcinoma have limited treatment options and a poor prognosis. The JAVELIN Bladder 100 trial showed that avelumab as first‐line maintenance plus best supportive care significantly prolonged overall survival and progression‐free survival versus best supportive care alone in patients with locally advanced or metastatic urothelial carcinoma that had not progressed with first‐line platinum‐containing chemotherapy. AIMS: We assessed whether avelumab plus best supportive care is a cost‐effective treatment option versus best supportive care alone in this patient group in Taiwan. METHODS AND RESULTS: A partitioned survival model was used to estimate the costs and effects of avelumab plus best supportive care versus best supportive care alone over a 20‐year time horizon from the perspective of Taiwan's National Health Insurance Administration. Patient‐level data from JAVELIN Bladder 100 on efficacy, safety, utility, and time on treatment were analyzed to provide parameters for the model. Log‐normal and Weibull distributions were used for overall survival and progression‐free survival, respectively. Costs of healthcare resources, drug acquisition, adverse events, and progression were identified through publicly available data sources and clinician interviews. The model estimated total costs, life years, and quality‐adjusted life years. In the modeled base case, avelumab plus best supportive care increased survival versus best supportive care alone by 0.79 life years (2.93 vs. 2.14) and 0.61 quality‐adjusted life years (2.15 vs. 1.54). The incremental cost‐effectiveness ratio for avelumab plus best supportive care versus best supportive care alone was NT$1 827 680. Most (78%) of the probabilistic sensitivity analyses fell below three times the gross domestic product per capita. Scenario analysis indicated that life year and quality‐adjusted life year gains were most sensitive to alternative survival extrapolations for both avelumab plus best supportive care and best supportive care alone. CONCLUSION: Avelumab first‐line maintenance therapy combined with best supportive care was determined as a cost‐effective treatment strategy for patients in Taiwan diagnosed with locally advanced or metastatic urothelial carcinoma that had not progressed with platinum‐containing chemotherapy.