CAR T-cell therapy appears cost-effective in pediatric leukemia

Tisagenlecleucel appears to be priced in line with its estimated long-term survival benefit among children and young adults with relapsed or refractory B-cell acute lymphoblastic leukemia, according to results of a cost-effectiveness analysis published in JAMA Pediatrics.

The chimeric antigen receptor (CAR) T-cell therapy tisagenlecleucel (Kymriah, Novartis) could be a novel and potentially curative treatment option for this patient population, among whom 5-year DFS is between 10% and 20%.

However, the therapy is expensive, with a current list price of $475,000 per one-time administration, according to study background.

Melanie D. Whittington, PhD, researcher in the department of clinical pharmacy at the University of Colorado Anschutz Medical Campus, and colleagues sought to assess the long-term survival outcomes and value of tisagenlecleucel compared with clofarabine monotherapy.

The researchers created a decision analytic model with data pooled from three studies — B2101J (enrolled patients between March 2012 and November 2015), B2205J (enrolled patients between August 2014 and February 2016), and B2202 (enrolled patients between April 2015 and November 2016).

Researchers used flexible parametric modeling from the direct extrapolation of EFS and OS curves to derive survival outcomes of patients aged younger than 25 years with B-cell ALL that is refractory or in second or later relapse.

Clinical inputs included survival, adverse effects and quality of life. Economic inputs included treatment acquisition cost, potential hospital markup and health care use.

Life-years gained, quality-adjusted life-years (QALYs) gained, and incremental costs per life-year and QALY gained served as primary endpoints.

Researchers estimated 40% of patients initiating tisagenlecleucel treatment would be long-term survivors, compared with 10.8% of patients receiving clofarabine.

The total discounted cost of tisagenlecleucel was $667,000, with 10.34 discounted life-years gained and 9.28 QALYs gained. Clofarabine had a total discounted cost of approximately $337,000, with 2.43 discounted life-years gained and 2.1 QALYs gained.

Compared with clofarabine, tisagenlecleucel had an incremental cost-effectiveness ratio of nearly $42,000 per life-year gained and nearly $46,000 per QALY gained.

Results of a sensitivity analysis that used more conservative assumptions regarding long-term relapse and survival showed an incremental cost effectiveness ratio that ranged from $37,000 to $78,000 per QALY gained.

“This study suggests that payers and innovators should develop novel payment models that reduce the risk and uncertainty around long-term value and provide safeguards to ensure high-value care,” the researchers wrote.

In an accompanying editorial, Lisa A. Prosser, PhD, director of the Child Health Evaluation and Research Center, and professor in the department of pediatrics and communicable diseases at the University of Michigan, suggested the value framework should not necessarily be adjusted for high-cost treatments.

“Rather, the treatment should deliver clinical gains sufficient to justify its price,” she wrote. “If we continue to adjust frameworks for treatments that are expensive but not sufficiently effective, we may find that the tradeoffs necessary to accommodate these new interventions may be more than we bargained for.” – by Jennifer Southall

Disclosures: The study was funded by the Institute for Clinical and Economic Review. Prosser and Whittington report no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.