Patients Express Concerns Over Costs, Risks of Gene Therapies for Sickle Cell Disease

Patients with sickle cell disease recently gained two new treatment options with the approval of the gene therapies Casgevy (exagamglogene autotemcel) and Lyfgenia (lovotibeglogene autotemcel). However, uptake of these therapies has lagged with only a small group of patients starting the process of receiving these gene therapies.

Gene therapy is a cost-effective treatment in the long-term, but it remains an “expensive and intensive treatment option,” explained authors of an abstract presented at the 2024 American Society of Hematology (ASH) Annual Meeting. They assessed perception and knowledge of gene therapies among patients with sickle cell disease and their caregivers through a survey, which was completed by 49 participants. The three-part survey covered demographic information and current understanding of gene therapies in part one, education on gene therapies in part two and patient/caregiver willingness to receive gene therapies in part three.

The majority (65.3%) of respondents were patients with the rest being caregivers responding on behalf of a patient. Roughly one-third (32.7%) of responses were pediatric patients. Half (49.0%) of patients reported 3 or more visits to the emergency room in the last two years because of their sickle cell disease. Most patients reported acute (81.6%) and/or chronic (57.1%) pain and 46.9% said they experienced pain daily or weekly. Most (83.7%) of the patients were receiving disease-modifying therapy for their sickle cell disease.

While a majority (75.5%) of respondents said they were aware of gene therapies for sickle cell disease, 59.2% said they felt “not at all knowledgeable” or only “slightly knowledgeable” about gene therapies. The primary sources of their information about gene therapy were the medical team (54.1%) and media (40.5%).

The top concern about gene therapy was the risk of cancer (77.6%) followed by financial consequences (67.3%), infection (63.3%), unanticipated side effects (57.1%) and infertility (51.0%).

“Interestingly, 2 in 3 patients had concerns about the financial toxicity of gene therapy beyond the cost of the product itself, highlighting the short- and long-term burden of these therapies,” the researchers noted.

After the education portion of the survey, respondents said they felt more knowledgeable and perceived gene therapies as safer, but the interest in receiving treatment essentially remained unchanged with only equal proportions saying “no” or “yes” (24.5% each) to receiving gene therapies and the majority (51.0%) saying “maybe.”

“Understanding knowledge gaps and perceptions of gene therapy among patients/caregivers can inform how physicians approach conversations about treatment options and can help align research questions with patients’ needs,” the authors concluded.

A separate abstract at ASH performed a cost-effectiveness analysis of non-myeloablative/reduced intensity conditioning haploidentical allogeneic-hematopoietic stem cell transplantation (NMAC/RIC-HID allo-HSCT), gene therapy and standard of care for young adults with sickle cell disease. They conducted the analysis using a four-arm Markov model that assumed the best-reported performance for each strategy and 100% effectiveness for gene therapy (at a $2.1 million cost for treatment).

In the base-case, NMAC/RIC-HID allo-HSCT accrued 22.6 discounted lifetime quality-adjusted life-years (QALYs) at a discounted cost of $1.0 million, gene therapy accrued 24.3 discounted lifetime QALYs at a discounted cost $2.5 million and standard care accrued 14.3 discounted lifetime QALYs at a discounted cost of $1.0 million.

The probabilistic sensitivity analysis determined NMAC/RIC-HID allo-HSCT was the most cost-effective strategy in 100% of the 10,000 iterations. The incremental net monetary benefit of NMAC-RIC-HID allo-HSCT was $810,000 compared with standard care and $1.3 million compared with gene therapy.

“With advancements in NMAC/RIC-HID allo-HSCT outcomes in adults with [sickle cell disease], allotransplantation offers a cost-effective therapeutic option for lifelong disease amelioration for people living with [sickle cell disease],” the authors concluded.