OBJECTIVES:

This study aimed to evaluate the cost-effectiveness of 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 GRID trial (regorafenib plus BSC vs. placebo plus BSC in patients with previous failure of at least two drugs, including both imatinib and sunitinib). Cost and utility values were derived from previous studies, the Chinese Drug Bidding Database and health-care documents. Sensitivity analyses were performed to observe model stability.

RESULTS:

In the PS model, regorafenib plus BSC yielded an additional 0.05 quality-adjusted life-years (QALYs) with an incremental cost of 18,233 USD; the incremental cost-effectiveness ratio (ICER) was 394,773 USD/QALY. In the one-way sensitivity analysis, it was seen that the utilities in the model (progression-free (PF) utility of regorafenib + BSC, PF BSC utility, postprogression (PP) utility) were the main model drivers in the model. In the probabilistic sensitivity analysis (PSA), the probability that regorafenib plus BSC would be cost-effective was 0% if the willingness-to-pay threshold was $10,805/QALYs~$32,415/QALYs (1-3 times the GDP per capita in 2020).

CONCLUSIONS:

The findings of the present analysis suggest that regorafenib plus BSC provides additional progression-free survival (PFS) benefit but is not cost-effective compared to BSC for patients with metastatic or unresectable gastrointestinal stromal tumors in China based on the currently available clinical data.