LAUSR

PURPOSE Patients with BCG-unresponsive carcinoma in situ (CIS) are treated with radical cystectomy (RCx) or salvage intravesical chemotherapy (SIC). Recently, pembrolizumab was approved for BCG-unresponsive CIS. MATERIALS AND METHODS We used a decision-analytic Markov model to compare pembrolizumab, SIC (with gemcitabine-docetaxel induction+monthly maintenance), and RCx for patients with BCG-unresponsive CIS who are RCx candidates (index patient 1) or are unwilling/unable to undergo RCx (index patient 2). The model used a US Medicare perspective with a 5-year time horizon. One-way and probabilistic sensitivity analyses were performed. Incremental Cost-Effectiveness Ratios(ICERs) were compared using a willingness-to-pay threshold of $100,000/Quality-adjusted life year(QALY). RESULTS For index patient 1, pembrolizumab was not cost-effective relative to RCx(ICER $1,403,008/QALY) or SIC(ICER $2,011,923/QALY). One-way sensitivity analysis revealed that pembrolizumab only became cost-effective relative to RCx with a >93% price reduction. Relative to RCx, SIC was cost-effective for time horizons <5 years and nearly cost-effective at 5 years(ICER $118,324/QALY). One-way sensitivity analysis revealed that SIC became cost-effective relative to RCx if risk of recurrence or metastasis at 2 years was less than 55% or 5.9%, respectively. For index patient 2, pembrolizumab required >90% price reduction to be cost-effective(ICER $1,073,240/QALY). Pembrolizumab was cost-effective in 0% of 100,000 microsimulations in probabilistic sensitivity analyses for both index patients. CONCLUSIONS At its current price, pembrolizumab is not cost-effective for BCG-unresponsive CIS relative to RCx or SIC. Although gemcitabine-docetaxel is not cost-effective relative to RCx at 5 years, further studies may validate its cost-effectiveness if recurrence and metastasis thresholds are met.