Cost-Effectiveness of Nivolumab-Ipilimumab Combination Therapy Compared with Monotherapy for First-Line Treatment of Metastatic Melanoma in the United States.

BACKGROUND The approval of new immunotherapies has dramatically changed the treatment landscape of metastatic melanoma. These survival gains come with trade-offs in side effects and costs, as well as important considerations for third-party payer systems, physicians, and patients. OBJECTIVE To develop a Markov model to determine the cost-effectiveness of nivolumab, ipilimumab, and nivolumab-ipilimumab combination as firstline therapy in metastatic melanoma, while accounting for differential effectiveness in programmed death-ligand 1 (PD-L1) positive and negative patients. METHODS A 3-state Markov model (PD-L1 positive stable disease, PD-L1 negative stable disease, and progression and/or death) was developed using a U.S. societal perspective with a lifetime time horizon of 14.5 years. Transition probabilities were calculated from progression-free (PF) survival data reported in the CheckMate-067 trial. Costs were expressed in 2015 U.S. dollars and were determined using national sources. Adverse event (AE) management was determined using immune-related AE (irAE) data from CheckMate-067, irAE management guides for nivolumab and ipilimumab, and treatment guidelines. Utilities were obtained from published literature, using melanoma-specific studies when available, and were weighted based on incidence and duration of irAEs. Base case, one-way sensitivity, and probabilistic sensitivity analyses were conducted. RESULTS Nivolumab-ipilimumab combination therapy was not the cost-effective choice ($454,092 per PF quality-adjusted life-year [QALY]) compared with nivolumab monotherapy in a base case analysis at a willingness-to-pay threshold of $100,000 per PFQALY. Combination therapy and nivolumab monotherapy were cost-effective choices compared with ipilimumab monotherapy. PD-L1 positive status, utility of nivolumab and combination therapy, and medication costs contributed the most uncertainty to the model. In a population of 100% PD-L1 negative patients, nivolumab was still the optimal treatment, but combination therapy had an improved incremental cost-effectiveness ratio (ICER) of $295,903 per PFQALY. Combination therapy became dominated by nivolumab, when 68% of the sample was PD-L1 positive. In addition, the cost of ipilimumab would have to decrease to < $21,555 per dose for combination therapy to have an ICER < $100,000 per PFQALY and to < $19,151 (a 42% reduction) to be more cost-effective than nivolumab monotherapy. CONCLUSIONS Nivolumab-ipilimumab combination therapy was not cost-effective compared with nivolumab monotherapy, which was the most cost-effective option. Professionals in managed care settings should consider the pharmacoeconomic implications of these new immunotherapies as they make value-based formulary decisions, and future cost-effectiveness studies are completed. DISCLOSURES No funding supported this study. Merino was a contractor with EMD Serono at the time of this study but does not have any conflicts of interest and did not receive any funding related to this study. All other authors have no financial disclosures and no conflicts of interest. All the authors contributed to the study concept and design. Tran, McDowell, and Barcelon took the lead in data collection, along with Oh, Keyvani, and Merino. All authors except Merino contributed to data interpretation. The manuscript was written by Oh, Tran, McDowell, and Wilson and revised by Oh, Tran, McDowell, Wilson, and Keyvani. This analysis was presented at Academy of Managed Care Pharmacy Managed Care & Specialty Pharmacy Annual Meeting 2016, April 19-22, 2016, in San Francisco, California, and at the International Society for Pharmacoeconomics and Outcomes Research Annual International Meeting, May 21-25, 2016, in Washington DC.