Cost effectiveness of combination ipilimumab-nivolumab in advanced non-small-cell lung cancer.

e19387 Background: The combination of nivolumab and ipilimumab was found to improve overall survival compared to chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC) in the Checkmate 227 trial. However, nivolumab and ipilimumab are significantly more expensive than chemotherapy, and given the high incidence of advanced lung cancer, incorporating dual checkpoint inhibitors into the standard of care could have substantial economic consequences. In this study, we evaluated the cost effectiveness of combination ipilimumab and nivolumab for the treatment of advanced NSCLC. Methods: We designed a Markov model simulating the three treatment arms of the Checkmate 227 trial: nivolumab plus ipilimumab, nivolumab monotherapy, and chemotherapy. Transition probabilities, such as disease progression, survival, and treatment toxicities, were derived from trial data. Costs (in 2019 United States dollars) and health utilities were estimated from published literature. Incremental cost-effectiveness ratios (ICERs), expressed as dollar per quality-adjusted life-year (QALY), were calculated, with results less than $100,000/QALY considered cost-effective from a healthcare payer perspective. We assessed model uncertainty with one-way and probabilistic sensitivity analyses. Results: In our base-case model, nivolumab and ipilimumab combination therapy increased overall cost by $227,700 and improved effectiveness by 0.55 QALY compared to chemotherapy, resulting in an ICER of $413,400/QALY. Nivolumab monotherapy increased overall cost by $98,500 and improved effectiveness by 0.05 QALY compared to chemotherapy, resulting in an ICER of $1,885,400/QALY. Our model was most sensitive to both the cost and duration of dual immunotherapy. Combination immunotherapy became cost effective at an ICER under $100,000/QALY if monthly costs of treatment were reduced from $26,586 to $8,844 (a 67% reduction) or if maximum allowed duration of immunotherapy was reduced from 24 to 4 months. The model was not sensitive to assumptions about survival differences between the study arms. Probabilistic sensitivity analysis showed that at a willingness-to-pay threshold of $100,000/QALY, dual immunotherapy was less cost-effective than chemotherapy 99.99% of the time. Conclusions: Combination nivolumab and ipilimumab immunotherapy is not cost-effective at current prices despite increasing overall survival for patients with advanced NSCLC.