OBJECTIVES

: This study aimed to evaluate the cost-effectiveness of pazopanib versus regorafenib as a third-line treatment for metastatic or unresectable gastrointestinal stromal tumors in China.

METHODS

: The partitioned survival (PS) model was used, and the study included 3 health states over the period of a lifetime. Survival information and safety data were derived from the PAZOGIST trial (pazopanib plus BSC vs. placebo plus BSC) and GRID trial (regorafenib plus BSC vs. placebo plus BSC). Cost and utility values were derived from previous studies, the Chinese Drug Bidding Database, and healthcare documents. The sensitivity analyses and scenario analysis were performed to observe model stability.

RESULTS

: In the PS model, pazopanib yielded a subtractive 0.28 quality-adjusted life-years (QALYs) with a decremental cost of 10,180 USD; the incremental cost-effectiveness ratio (ICER) was $36,480/QALY. In the one-way sensitivity analysis, it was seen that the cost of regorafenib, the cost of pazopanib and the cost of BSC per cycle were the main model drivers in the model. In the probabilistic sensitivity analysis (PSA), the probability that pazopanib would be cost-effective was 77%~100% if the willingness-to-pay threshold was $11,267/QALYs ~ $33,801/QALYs (1-3 times the GDP per capita in 2020). In the scenario analysis where the OS values of the pazopanib and regorafenib were the same, the base case ICER was $67,375/QALYs and the probability that pazopanib would be cost-effective was 88%~100% if the willingness-to-pay threshold was $11,267/QALYs ~ $33,801/QALYs

CONCLUSIONS

: The findings of the present analysis suggest that pazopanib provides subtractive progression-free survival (PFS) benefits but is more cost-effective compared to regorafenib for patients with metastatic or unresectable gastrointestinal stromal tumors in China based on the currently available clinical data.