Mark Walters, MD, on the Future of Sickle Cell Disease’s Landscape of Care

“Doctors and comprehensive healthcare teams will play a principal role in the decision-making process for patients considering the autologous gene therapies that are now approved and available. This involves carefully balancing the risks and benefits of the treatment, both in the short-term and the long-term, and understanding there's a potential for long-term side effects that aren't very well or are not understood at all right now that will have to be considered when making a decision about whether to pursue them.”

Vertex Pharmaceuticals' and CRISPR Therapeutics’ exagamglogene autotemcel (exa-cel; marketed as Casgevy) and bluebird bio’s lovotibeglogene autotemcel (lovo-cel; marketed as Lyfgenia) were both approved by the FDA for the treatment of sickle cell disease (SCD) in December 2023. The 2 new therapies, which both involve genetic modification of patients own blood stem cells, have provided important new curative treatment options for a disease that previously could only be cured with allogeneic stem cell transplant, which requires a compatible donor and carries the risk of graft versus host disease.

In June 2024, CGTLive® reached out to Mark Walters, MD, a professor in residence for pediatrics at the Sickle Cell Center of Excellence at the University of California, San Francisco, to learn more about how exa-cel and lovo-cel are changing the landscape of care for SCD. Walters gave an overview of what the treatment landscape looks like for SCD in 2024, and spoke about the advantages and drawbacks of the 2 gene therapy products in comparison to allogeneic transplant, noting that the cost of the gene therapy products may hinder their accessibility to patients. Walters additionally discussed how doctors and healthcare teams will now need to help patients decide the optimal treatment path for patients with SCD, noting that mental health professionals may play an important role in this process. He concluded by discussing some investigational SCD treatments that remain on the horizon but may eventually alter the treatment landscape further, such as in vivo approaches to gene therapy.

REFERENCES
1. FDA Approves First Gene Therapies to Treat Patients with Sickle Cell Disease. News release. FDA. December 7, 2023. Accessed July 1, 2024. https://www.fda.gov/news-events/press-announcements/fda-approves-first-gene-therapies-treat-patients-sickle-cell-disease