Gene Therapy Adoption in Hematology Remains Selective

EXTON, Pa. – October 2, 2025 – A newly released report, Special Topix: Adoption and Impact of Gene Therapy in Hematology, reveals that physicians are adopting gene therapies for hematologic conditions, including sickle cell disease (SCD), beta-thalassemia, and hemophilia A and B, in a highly selective phase. While gene therapy offers the promise of a cure, real-world uptake is heavily constrained by practical barriers like cost, reimbursement hurdles, conditioning regimen toxicity, and a lack of long-term durability data.

Physicians Define a “Narrow Archetype”

Physicians consistently describe the ideal candidate for gene therapy as a patient who is younger, highly motivated, and either severely disease-burdened (in SCD) or poorly controlled on standard care (in thalassemia).

Brand and Indication Preferences:

• Hemoglobinopathies: Among the options, Casgevy is emerging as the favored option over Lyfgenia and Zynteglo, with hematologists citing greater confidence in the underlying CRISPR/Cas9 technology and a more favorable payer outlook.
• Hemophilia: Physicians show more enthusiasm for Hemgenix (Hemophilia B) over Roctavian (Hemophilia A), noting stronger durability perceptions and fewer concerns about long-term liver toxicity with Hemgenix. Enthusiasm for Hemophilia A gene therapy is muted due to the reliable availability of non-gene therapy options and concerns over declining factor expression over time.

Despite clear preferences, overall referrals and actual prescribing remain limited, highlighting the gap between clinical excitement and real-world implementation.

Patient willingness and Future Outlook

The study found a disconnect between physician readiness and patient willingness, particularly in SCD. Physicians note frequent patient reluctance due to the burdens of busulfan-based myeloablative conditioning and fear of the unknown. Conversely, many hemophilia patients are motivated but are cautioned by their physicians about logistical challenges and the fact that gene therapy is not always a permanent cure.

Looking ahead, hematologists anticipate that only about one-third of their eligible patients across these conditions will ultimately receive gene therapy within the next few years. This signals a meaningful but measured integration into the standard treatment paradigm.

To accelerate adoption, the report suggests stakeholders must urgently address the tangible barriers: provide transparent durability data, establish supportive reimbursement frameworks, streamline treatment logistics, and expand patient education to overcome hesitancy.

Spherix will further explore these underlying drivers in an upcoming whitepaper co-authored with Dr. Steven Pipe and Dr. Haydar Frangoul.