Gene Therapy Versus Common Care for Eligible Individuals With Sickle Cell Disease in the United States A Cost-Effectiveness Analysis

Background: Sickle cell disease (SCD) and its complications contribute to high rates of morbidity and early mortality and high cost in the United States and African heritage community. Objective: To evaluate the cost-effectiveness of gene therapy for SCD and its value-based prices (VBPs). Design: Comparative modeling analysis across 2 independently developed simulation models (University of Washington Model for Economic Analysis of Sickle Cell Cure [UW-MEASURE] and Fred Hutchinson Institute Sickle Cell Disease Outcomes Research and Economics Model [FH-HISCORE]) using the same databases. Data Sources: Centers for Medicare & Medicaid Services claims data, 2008 to 2016; published literature. Target Population: Persons eligible for gene therapy. Time Horizon: Lifetime. Perspective: U.S. health care sector and societal. Intervention: Gene therapy versus common care. Outcome Measures: Incremental cost-effectiveness ratios (ICERs), equity-informed VBPs, and price acceptability curves. Results of Base-Case Analysis: At an assumed $2 million price for gene therapy, UW-MEASURE and FH-HISCORE estimated ICERs of $193 000 per QALY and $427 000 per QALY, respectively, under the health care sector perspective. Corresponding estimates from the societal perspective were $126 000 per QALY and $281 000 per QALY. The difference in results between models stemmed primarily from considering a slightly different target population and incorporating the quality-of-life (QOL) effects of splenic sequestration, priapism, and acute chest syndrome in the UW model. From a societal perspective, acceptable (>90% confidence) VBPs ranged from $1 million to $2.5 million depending on the use of alternative effective metrics or equity-informed threshold values. Results of Sensitivity Analysis: Results were sensitive to the costs of myeloablative conditioning before gene therapy, effect on caregiver QOL, and effect of gene therapy on long-term survival. Limitation: The short-term effects of gene therapy on vaso-occlusive events were extrapolated from 1 study. Conclusion: Gene therapy for SCD below a $2 million price tag is likely to be cost-effective when applying a societal perspective at an equity-informed threshold for cost-effectiveness analysis. Primary Funding Source: National Heart, Lung, and Blood Institute.