Qualitative Interview Study to Characterize the Treatment Experiences of Participants with Sickle Cell Disease and Assess Perceptions of Red Blood Cell Transfusions

Introduction:Sickle cell disease (SCD), an inherited hemoglobinopathy, is caused by a β-globin gene (HBB) mutation that produces sickle hemoglobin (HbS). Polymerization of HbS results in sickling of red blood cells (RBCs), hemolysis, anemia, and vaso-occlusive crises (VOCs). Use of RBC transfusions is common to mitigate the impact of severe complications of SCD, but not without risk (eg, iron overload, alloimmunization). Although new and future treatments may reduce the need for transfusions, little evidence exists on what patients with SCD perceive as meaningful in relation to changing the frequency and/or volume of RBC transfusions. We report the treatment experiences and perceived burden of RBC transfusions in adults with SCD.

Methods:Using a semi-structured interview guide, experienced interviewers conducted individual web-based interviews with 20 adults with SCD in February and March 2024. All study participants provided consent and met the study eligibility criteria, which included a diagnosis of SCD from a healthcare provider (HCP), previously received RBC transfusions for the treatment of SCD, resided in the US, and spoke English. Individuals were excluded from participation for self-reported history of stroke. Each interview lasted up to 1 hour, was audio-recorded, and transcribed verbatim to facilitate analysis. Participants were asked questions about the importance of reducing the frequency and volume of RBC transfusions, meaningfulness of changes (both reductions and increases) in RBC transfusions, and preference for taking once-daily pills instead of receiving RBC transfusions. RTI International's institutional review board reviewed the study materials and provided a research exemption.

Results:Among the 20 participants, the mean (SD) age was 35.9 (8.3) years, 15 (75%) were female, 19 (95%) were Black, 8 (40%) had college degrees, and 8 (40%) were receiving disability. One participant did not finish the interview. The self-reported average frequency of RBC transfusions was 3.4 times a year (range, 0-12) by the 15 participants who had received ≥1 RBC transfusion in the past year for the treatment of SCD, 19/20 (95%) reported their HCP recommended hydroxyurea (HU), and 8/19 (42%) reported current HU use. Although RBC transfusions were associated with perceived benefits (eg, increased energy, decreased pain, increased Hb), 13/20 participants (65.0%) reported fears or worries about developing associated complications such as iron overload, infections, and alloimmunization. Of 19 respondents,16 (84.2%) reported it was “extremely important” or “very important” to reduce the frequency of RBC transfusions and 9 (47.4%) responded that it was “extremely important” or “very important” to reduce the volume of RBC transfusions. Primarily because of associated risks, no participant reported that an increase in the frequency of RBC transfusions would be meaningful. Most of the 19 respondents (12; 63.2%) reported that the prevention of RBC transfusions (n=5) or a reduction of 1 (n=3) or 2 (n=4) RBC transfusions per year would be meaningful. Most respondents (14/19; 73.7%) rated the likelihood of choosing once-daily pills over receiving RBC transfusions as ≥8 on a scale from 0 to 10 (0=“not at all”, 10=“extremely”). Reasons for choosing pills included “more convenient”; “to cut down on hospitalizations and blood transfusions”; “less worry about liver damage, kidney failure”; and “it will increase [the quality of] my life.”

Conclusions:Future SCD treatments are needed to help mitigate the burden of RBC transfusions based on patient experiences and preferences. The complications associated with RBC transfusions coupled with the significant costs to individuals and the healthcare system reveal unmet needs with respect to SCD options.

Kosa:RTI Health Solutions: Current Employment; Pfizer: Research Funding. Vanegas:Pfizer: Research Funding; RTI Health Solutions: Current Employment. Colavecchia:Pfizer: Current Employment, Current equity holder in publicly-traded company. Coulter:Pfizer: Current Employment, Current equity holder in publicly-traded company. Christopher:Pfizer: Current Employment, Current equity holder in publicly-traded company. Fasano:Pfizer: Honoraria. Chou:Pfizer: Honoraria. Drachtman:Pfizer: Honoraria; Bluebird Bio: Honoraria; Jazz: Honoraria; Agios: Honoraria. Purdie:Pfizer: Current Employment, Current equity holder in publicly-traded company. Baker:Pfizer: Current Employment, Current equity holder in publicly-traded company. Meier:Pfizer: Current Employment, Current equity holder in publicly-traded company.