Tisagenlecleucel cost-effective for young adults with relapsed acute lymphoblastic leukaemia

For young adults with relapsed/refractory acute lymphoblastic leukaemia (R/R ALL) who had failed at least two prior lines of therapies, tisagenlecleucel appears to be an inexpensive treatment option, according to a recent Singapore study.

“Provision of coverage for tisagenlecleucel treatment costs is likely to represent good use of healthcare resources by facilitating the access of this effective treatment to patients in Singapore,” the researchers said. “A funding solution on this one-off therapy may require a multi-party partnership involving governments, insurers, hospitals, and pharmaceutical company, considering the multi-payer system in Singapore.”

Using a three-health state partitioned survival model, the cost-effectiveness of tisagenlecleucel was compared with salvage chemotherapy regimen (SCR) or blinatumomab (BLN), drawing data from prior trials. The incremental cost-effectiveness ratio (ICER) was estimated as the incremental costs per quality-adjusted life-year (QALY) gained, taking side effects, follow-up, subsequent relapse, and other outcomes into consideration.

The base-case analysis revealed that tisagenlecleucel resulted in a mean QALY gain of 9.87 vs SCR and 7.50 vs BLN over a lifetime horizon. Such benefits were achieved at corresponding incremental costs of SGD 452,317 and SGD 389,679. [Clinicoecon Outcom Res 2022;14:333-355]

The resulting ICER per QALY gained was SGD 45,840 vs SCR and SGD 38,468 vs BLN. Despite steep upfront costs, the researchers deemed tisagenlecleucel to be cost-effective, leading to better QALY gain relative to BLN or SCR. Moreover, these upfront costs could be offset by the more frequent drug administrations, longer hospitalizations, and greater need for allogeneic stem cell transplant in BLN and SCR scenarios.

However, tisagenlecleucel was associated with more severe adverse events, which also contributed to the higher tisagenlecleucel costs overall.

Sensitivity analyses showed that the base-case ICER estimates were highly dependent on the cost of tisagenlecleucel, along with discount rates, time horizon of treatment, and rates of subsequent allogeneic stem cell transplant in SCR/BLN patients.

For instance, when the cost of tisagenlecleucel treatment was raised or lowered by 25 percent, its ICER relative to SCR ranged from SGD 34,871 to SGD 56,809. A similar analysis comparing tisagenlecleucel with BLN yielded an ICER range of SGD 37,541 to SGD 66,415.

“This cost-effectiveness analysis demonstrates that tisagenlecleucel treatment at a unit price of SGD 500K is a cost-effective option for R/R ALL among children and young adult patients when compared with SCR or BLN, from Singapore’s healthcare system perspective,” the researchers said.

“[Deterministic and probabilistic sensitivity analyses] support model robustness and validate our results, with 100-percent likelihood of tisagenlecleucel being cost-effective at an assumed willingness-to-pay threshold of three times the gross domestic product of Singapore,” they added.