KEY TAKEAWAYS
- The KEYNOTE-177 phase 3 trial aimed to evaluate the cost-effectiveness of pembrolizumab from the payer’s perspective.
- Despite treatment variations, the results revealed pembrolizumab’s cost-effectiveness over chemotherapy at a 15 million/QALY threshold.
Pembrolizumab significantly prolonged progression-free survival compared to chemotherapy for patients with advanced colorectal cancer with MSI-High or dMMR.
Taniguchi S and the team aimed to assess the cost-effectiveness of pembrolizumab from the perspective of payers in Japan.
The study utilized a partitioned survival analysis model to predict costs and quality-adjusted life years (QALYs) for individuals in the pembrolizumab and chemotherapy groups. Survival data were obtained from the Phase III KEYNOTE-177 study.
Drug prices were estimated based on Japan’s NHI drug pricing. Other cost parameters were estimated using the JMDC claims database. Utility weights were derived from previous studies. A lifetime horizon and a 2% discount rate were applied. The incremental cost-effectiveness ratio (ICER) of pembrolizumab compared to chemotherapy was estimated. Sensitivity analyses were conducted to assess parameter uncertainty.
The results revealed that the incremental cost of pembrolizumab compared to chemotherapy was estimated at -JPY 15,409,646, with an incremental QALY of 2.51, making pembrolizumab dominant. Without the 2-year discontinuation rule for pembrolizumab, the ICER was estimated at JPY 14,891,339/QALY.
If subsequent treatment costs in the chemotherapy arm excluded pembrolizumab, the ICER was estimated at JPY 1,157,159/QALY. After adjusting for the crossover effect with pembrolizumab on overall survival in the chemotherapy arm, the ICER was estimated at JPY 4,276,547/QALY.
The study found that despite variations in treatment duration with pembrolizumab and the subsequent treatment setting in the chemotherapy arm, pembrolizumab was cost-effective compared to chemotherapy when a willingness-to-pay threshold of 15 million/QALY was applied.
The trial was sponsored by the Merck Sharp & Dohme LLC.
Source: https://www.ispor.org/heor-resources/presentations-database/presentation/intl2024-3900/137491
Clinical Trial: https://classic.clinicaltrials.gov/ct2/show/NCT02563002
Taniguchi S, Moriwaki K, Morimoto K, et al. (2024). “Cost-Effectiveness Analysis of Pembrolizumab for Advanced Colorectal Cancer with MSI-High or dMMR in Japan.” Presented at ISPOR 2024.2024-05, ISPOR 2024, Atlanta, GA, USA. (EE508)
