The high price of chimeric antigen receptor (CAR) T-cell therapy for pediatric leukemia may prove cost effective if long-term survival benefits are realized, researchers reported.
A cost-effectiveness analysis of the CAR T-cell therapy tisagenlecleucel suggests that the $475,000 price tag is in alignment with the lifetime benefits of the treatment. The findings were published in.
Tisagenlecleucel – marketed as Kymriah – is a one-dose treatment for relapsed or refractory pediatric B-cell acute lymphoblastic leukemia (ALL) and the first CAR T-cell therapy approved by the Food and Drug Administration.
In this cost-effectiveness analysis, researchers used a decision analytic model that extrapolated the evidence from clinical trials over a patient’s lifetime to assess life-years gained, quality-adjusted life-years (QALYs) gained, and incremental costs per life-year and QALY gained. The comparator was the chemoimmunotherapeutic agent clofarabine.
While tisagenlecleucel has a list price of $475,000, researchers discounted the price by 3% and added several additional costs, such as hospital administration, pretreatment, and potential adverse events, to get to a total discounted cost of about $667,000. They estimated that 42.6% of patients were considered to be long-term survivors with tisagenlecleucel, 10.34 life-years would be gained, and 9.28 QALYs would be gained.
In comparison, clofarabine had a total discounted cost of approximately $337,000 (including an initial discounted price of $164,000 plus additional treatment and administrative costs), 10.8% of patients were long-term survivors, 2.43 life-years were gained, and 2.10 QALYs were gained in the model.
Overall, the mean incremental cost-effectiveness ratio was about $46,000 per QALY gained in this base-case model.
In analyses of different scenarios, such as a deeper discount, a different treatment start, or a different calculation of future treatment costs, the cost-effectiveness ratio varied from $37,000 to $78,000 per QALY gained.
“We acknowledge that considerable uncertainty remains around the long-term benefit of tisagenlecleucel owing to limited available evidence; however, with current evidence and assumptions, tisagenlecleucel meets commonly cited value thresholds over a patient lifetime horizon, assuming payment for treatment acquisition for responders at 1 month,” wrote, from the University of Colorado at Denver, Aurora, and her colleagues.
The authors noted that the clinical trial evidence for tisagenlecleucel came from single-arm trials, which made selection of a comparator challenging. Clofarabine was chosen because it had the most similar baseline population characteristics, but they acknowledged that blinatumomab was also frequently used as a treatment for these patients.
“We suspect that tisagenlecleucel would remain cost effective, compared with blinatumomab,” they wrote. “A study conducted by other researchers found the incremental cost-effectiveness ratio of tisagenlecleucel versus blinatumomab was similar to the incremental cost-effectiveness ratio of tisagenlecleucel versus clofarabine [i.e., $3,000 more per QALY].”
The authors suggested that uncertainties in the evidence should be considered as payers are negotiating coverage and payment for tisagenlecleucel.
“Novel payment models consistent with the present evidence may reduce the risk and uncertainty in long-term value and be more closely aligned with ensuring high-value care,” they wrote. “Financing cures in the United States is challenging, owing to the high up-front price, rapid uptake, and uncertainty in long-term outcomes; however, innovative payment models are an opportunity to address some of these challenges and to promote patient access to novel and promising therapies.”
The study was funded by the Institute for Clinical and Economic Review, which receives some funding from the pharmaceutical industry. Four authors are employees of the Institute for Clinical and Economic Review.
SOURCE: Whittington MD et al. JAMA Pediatr. 2018 Oct 8. .