Cost-utility analysis of pembrolizumab versus nivolumab in the treatment of metastatic colorectal cancer from the perspective of the healthcare payer.

Abstract

Background: Colorectal cancer (CRC) is a malignant tumor with the third highest incidence worldwide. The comprehensive economic evaluation of programmed cell death protein-1 inhibitors in China, however, has not yet been carried out. The aim of this study is to assess the cost-utility of pembrolizumab and nivolumab in the treatment of metastatic colorectal cancer (mCRC).

Materials and methods: A Markov model microsimulation of efficacy and cost-utility analysis (CUA) was carried out, and efficacy and safety data were compared using network meta-analysis. Literature screening and data extraction were performed according to established criteria where the main outcome indicators, complete response (CR), partial response (PR), stable disease (SD), and progressive disease (PD) were compared between two treatments. The lifetime cost and outcomes of mCRC treatment were estimated, and quality-adjusted life years (-QALYs) and incremental cost-effectiveness ratio (ICER) were used to evaluate the economy of each program.

Results: A total of 442 studies were evaluated of which 15, with a total of 798 patients, were included in the analysis. Of these, 13 evaluated PD, and total patients for CR, PR, SD, and PD were 82, 283, 160, and 180 respectively. The corresponding heterogeneity values were (p = 0.13, heterogeneity index as percentage (I²) = 29.53%), (p < 0.01, I² = 72.55%), (p = 0.03, I² = 46.54%), (p < 0.01, I² = 80.31%), and (p = 0.13 > 0.05). The proportion of patients classified as CR in the pembrolizumab group was greater than in the nivolumab group (0.105 vs. 0.085). However, the number of patients classified as PR and SD in the nivolumab group exceeded those in the pembrolizumab group. The number of patients classified as PD were similar in the two groups. Combination therapy nivolumab + ipilimumab yielded an incremental gain of 0.04 QALYs at an additional cost of 356,723 ¥. The ICER reached 8,918,075 ¥/QALYs, surpassing three times the per capita gross domestic product (GDP).

Conclusion: Both pembrolizumab and nivolumab showed beneficial effects in patients with mCRC. Nivolumab in combination with ipilimumab led to improved progression-free survival, but the values for ICER reached 8,918,075 ¥/QALYs. Treatment of non-resectable or metastatic microsatellite instability-high (MSI-H)/deficient mismatch repair (dMMR) advanced solid tumors CRC with pembrolizumab alone, in the Chinese population examined, was the most cost-effective, where the willingness-to-pay threshold was 242,928 ¥/QALY (100 ¥ = 13.75 US$ and 12.63 €).