Cost-effectiveness analysis of durvalumab, tremelimumab, and etoposide-platinum in first-line treatment of extensive-stage small cell lung cancer.

Background: Durvalumab plus etoposide-platinum (DEP) showed sustained overall survival improvements in patients with extensive-stage small-cell lung cancer (ES-SCLC) compared to etoposide-platinum (EP), but adding tremelimumab to DEP (DTEP) did not significantly improve outcomes. A third-party payer perspective is taken here to evaluate the cost-effectiveness of DTEP, DEP, and EP for ES-SCLC.

Methods: The cost-effectiveness was evaluated by partitioning survival models into 3 mutually exclusive health states. In this model, clinical characteristics and outcomes were obtained from the CASPIAN. Model robustness was evaluated through 1-way deterministic and probabilistic sensitivity analyses. Outcome measurements included costs, quality-adjusted life-years (QALYs), incremental cost-effectiveness ratio, life-years, incremental net health benefit, and incremental net monetary benefit. The analysis was conducted with a 10-year lifetime horizon in a United States setting.

Results: Compared with EP, DEP, and DTEP were associated with an increment of 0.480 and 0.313 life-years, and an increment of 0.247 and 0.165 QALYs, as well as a $139,788 and $170,331 increase in cost per patient. The corresponding ICERs were $565,807/QALY and $1033,456/QALY, respectively. The incremental net health benefit and incremental net monetary benefit of DEP or DTEP were -0.685 QALYs and -$102,729, or -0.971 QALYs and -$145,608 at a willingness to pay threshold of $150,000/QALY, respectively. Compared with DTEP, DEP was dominated. DTEP and DEP were 100% unlikely to be cost-effective if the willingness to pay threshold was $150,000/QALY. DEP was cost-effective compared to EP when durvalumab was priced below $0.994/mg. Compared with EP, DEP, and DTEP were unlikely to be considered cost-effective across all subgroups.

Conclusion: DEP and DTEP were not cost-effective options in the first-line treatment for ES-SCLC compared with EP, from the third-party payer perspective in the United States. Compared with DTEP, DEP was dominated.