Cost Effectiveness of Chimeric Antigen Receptor T-Cell Therapy in Relapsed or Refractory Pediatric B-Cell Acute...

The anti-CD19 chimeric antigen receptor T-cell therapy tisagenlecleucel was recently approved to treat relapsed or refractory pediatric acute lymphoblastic leukemia. With a one-time infusion cost of $475,000, tisagenlecleucel is currently the most expensive oncologic therapy. We aimed to determine whether tisagenlecleucel is cost effective compared with currently available treatments.

Markov modeling was used to evaluate tisagenlecleucel in pediatric relapsed or refractory acute lymphoblastic leukemia from a US health payer perspective over a lifetime horizon. The model was informed by recent multicenter, single-arm clinical trials. Tisagenlecleucel (under a range of plausible long-term effectiveness) was compared with blinatumomab, clofarabine combination therapy (clofarabine, etoposide, and cyclophosphamide), and clofarabine monotherapy. Scenario and probabilistic sensitivity analyses were used to explore uncertainty. Main outcomes were life-years, discounted lifetime costs, discounted quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (3% discount rate).

With an assumption of a 40% 5-year relapse-free survival rate, tisagenlecleucel increased life expectancies by 12.1 years and cost $61,000/QALY gained. However, at a 20% 5-year relapse-free survival rate, life-expectancies were more modest (3.8 years) and expensive ($151,000/QALY gained). At a 0% 5-year relapse-free survival rate and with use as a bridge to transplant, tisagenlecleucel increased life expectancies by 5.7 years and cost $184,000/QALY gained. Reduction of the price of tisagenlecleucel to $200,000 or $350,000 would allow it to meet a $100,000/QALY or $150,000/QALY willingness-to-pay threshold in all scenarios.

The long-term effectiveness of tisagenlecleucel is a critical but uncertain determinant of its cost effectiveness. At its current price, tisagenlecleucel represents reasonable value if it can keep a substantial fraction of patients in remission without transplantation; however, if all patients ultimately require a transplantation to remain in remission, it will not be cost effective at generally accepted thresholds. Price reductions would favorably influence cost effectiveness even if long-term clinical outcomes are modest.