Purpose: Patients with bacillus Calmette-Guérin-unresponsive carcinoma in situ are treated with radical cystectomy or salvage intravesical chemotherapy. Recently, pembrolizumab was approved for bacillus Calmette-Guérin-unresponsive carcinoma in situ.
Materials and methods: We used a decision-analytic Markov model to compare pembrolizumab, salvage intravesical chemotherapy (with gemcitabine-docetaxel induction+monthly maintenance) and radical cystectomy for patients with bacillus Calmette-Guérin-unresponsive carcinoma in situ who are radical cystectomy candidates (index patient 1) or are unwilling/unable to undergo radical cystectomy (index patient 2). The model used a U.S. Medicare perspective with a 5-year time horizon. One-way and probabilistic sensitivity analyses were performed. Incremental cost-effectiveness ratios were compared using a willingness to pay threshold of $100,000/quality-adjusted life year.
Results: For index patient 1, pembrolizumab was not cost-effective relative to radical cystectomy (incremental cost-effectiveness ratios $1,403,008/quality-adjusted life year) or salvage intravesical chemotherapy (incremental cost-effectiveness ratios $2,011,923/quality-adjusted life year). One-way sensitivity analysis revealed that pembrolizumab only became cost-effective relative to radical cystectomy with a >93% price reduction. Relative to radical cystectomy, salvage intravesical chemotherapy was cost-effective for time horizons <5 years and nearly cost-effective at 5 years (incremental cost-effectiveness ratios $118,324/quality-adjusted life year). One-way sensitivity analysis revealed that salvage intravesical chemotherapy became cost-effective relative to radical cystectomy 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 (incremental cost-effectiveness ratios $1,073,240/quality-adjusted life year). 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 bacillus Calmette-Guérin-unresponsive carcinoma in situ relative to radical cystectomy or salvage intravesical chemotherapy. Although gemcitabine-docetaxel is not cost-effective relative to radical cystectomy at 5 years, further studies may validate its cost-effectiveness if recurrence and metastasis thresholds are met.
Keywords: bladder cancer; cancer of urinary tract; cost-benefit analysis; immunotherapy.