Cost-effectiveness of gemcitabine + cisplatin vs. gemcitabine monotherapy in advanced biliary tract cancer

The ABC-02 trial demonstrated a statistically significant survival benefit associated with the addition of cisplatin to gemcitabine in the palliative treatment of advanced biliary tract cancer (BTC). Based on the ABC-02 findings, this analysis seeks to evaluate the cost-utility of adding cisplatin to standard gemcitabine therapy from a U.S. societal perspective.

A decision-analytic model was developed to estimate direct medical costs, patient time costs, and quality-adjusted life-years (QALYs) for two treatment strategies: (1) gemcitabine + cisplatin, (2) gemcitabine monotherapy. Model parameters were derived from the pivotal trial of gemcitabine + cisplatin in advanced BTC, published literature, and government sources. The model included trial-based adverse events and costs related to drug treatment, routine follow-up, adverse events, and post-progression care. The model results were examined using one-way and probabilistic sensitivity analyses (PSA).

Total QALYs for the gemcitabine + cisplatin and gemcitabine monotherapy strategies were 0.751 and 0.561, respectively. Total costs were $44,885 and $33,653 respectively. Relative to gemcitabine monotherapy, gemcitabine + cisplatin had an incremental cost-effectiveness ratio (ICER) of $59,480 per QALY gained. One-way sensitivity analyses found results to be sensitive to progression-free survival, overall survival, pre and post-progression health state utility values, and the cost of post-progression care. In the PSA, gemcitabine monotherapy had the highest probability of being cost-effective until a willingness-to-pay of $60,000, after which the gemcitabine + cisplatin strategy had the highest probability.

The results of this analysis suggest that in advanced BTC, the cisplatin + gemcitabine regimen is a cost-effective treatment alternative to gemcitabine monotherapy by currently accepted standards of willingness to pay.