OBJECTIVES:

Transfusion-dependent β-thalassemia (TDT) is a rare genetic disease that affects the production of healthy red blood cells. Conventional treatment involves regular blood transfusions and iron chelation, which is associated with potential adverse events and a substantial impact on quality of life. The only approved curative therapy is allogenic hematopoietic stem cell transplant (allo-HSCT), which carries the risk of complications, including graft-versus-host disease (GvHD). One novel treatment approach is gene therapy involving autologous stem cell transplant of the patient’s own genetically modified hematopoietic stem cells. As new treatments for TDT are introduced, cost-utility analyses are needed to examine their value. The purpose of this study was to estimate utilities associated with treatment for TDT.

METHODS:

General population respondents in England valued eight health state vignettes (developed based on literature review and clinician, patient, and parent interviews) in time trade-off interviews. There were two pre-transplant health states, three health states describing the year in which a transplant occurs, and three post-transplant health states.

RESULTS:

A total of 207 participants completed interviews (49.8% female; mean age = 43.2 years; Newcastle, n=87; London, n=72; Bristol, n=48). Mean (SD) utilities for the pre-transplant health states were 0.73 (0.25) for transfusion with oral chelation and 0.63 (0.32) for transfusion with subcutaneous chelation. Mean utilities for the transplant year were 0.62 (0.35) for gene therapy, 0.47 (0.39) for allo-HSCT, and 0.39 (0.39) for allo-HSCT with acute GvHD. Post-transplant utilities were 0.93 (0.15) for transfusion independent, 0.75 (0.25) for 60% transfusion reduction, and 0.51 (0.38) for chronic GvHD. Acute and chronic GvHD were associated with significant disutility (acute = -0.09, p<0.0001; chronic = -0.43, p<0.0001).

CONCLUSIONS:

Utilities followed expected patterns, with more difficult TDT treatment processes associated with lower health state utilities. These utilities may be useful in cost-utility models estimating the value of treatments for TDT.