TOPLINE: 

Exagamglogene autotemcel (exa-cel), a CRISPR/Cas9 gene-edited cell therapy, eliminated vaso-occlusive crises in 97% of participants with severe sickle cell disease. The therapy led to substantial improvements in health-related quality of life (HRQOL) measures across physical, emotional, and social domains in both adults and adolescents.

METHODOLOGY:

• Researchers conducted a phase 3 trial (CLIMB SCD-121) involving 42 participants (30 adults and 12 adolescents) with severe sickle cell disease, defined as having greater than two severe vaso-occlusive crises per year in the previous 2 years.
• Patient-reported outcome (PRO) measures included EuroQol Quality of Life Scale-5 dimensions-5 levels, Functional Assessment of Cancer Therapy-Bone Marrow Transplantation, Adult Sickle Cell Quality of Life Measurement Information System, and 11-point pain Numerical Rating Scale for adults.
• Participants received plerixafor for hematopoietic stem and progenitor cell mobilization, followed by myeloablative conditioning with pharmacokinetically adjusted busulfan before exa-cel infusion.
• Analysis included follow-up data for up to 36 months for adults and up to 24 months for adolescents, with a median follow-up duration of 33.6 months.

TAKEAWAY:

• Adult EuroQol Quality of Life Scale scores showed substantial improvements by month 6 post-infusion (mean difference, 17.7; SD, 26.5) and health utility US index score (mean difference, 0.1; SD, 0.2), maintained through month 36.
• Functional Assessment of Cancer Therapy-General score demonstrated significant improvement by month 6 (mean difference, 13.7; SD, 18.9) and was sustained through month 36 (mean difference, 19.2; SD, 24.1).
• All Adult Sickle Cell Quality of Life Measurement Information System domains showed clinically meaningful improvements at month 36, including pain impact (mean difference, 8.1; SD, 7.9), emotional impact (mean difference, 8.5; SD, 7.8), and social functioning (mean difference, 16.5; SD, 9.8).
• Adolescents experienced similar improvements, with the Pediatric Quality of Life Inventory (PedsQL) total score increasing by month 6 (mean difference, 23.0; SD, 18.2) and maintaining through month 24 (mean difference, 30.4; SD, 16.8).

IN PRACTICE:

“Exa-cel led to broad and clinically meaningful HRQOL benefits in adults and adolescents with SCD [sickle cell disease]. Following exa-cel infusion, there were clinically meaningful improvements in all PRO measures assessed in both adult and adolescent participants, including improvements in overall health and general well-being, as well as specific improvements in physical, emotional, and social functioning well-being and pain experience,” the authors of the study wrote.

SOURCE:

This study was led by Akshay Sharma, St. Jude Children’s Research Hospital in Memphis, and Haydar Frangoul, Sarah Cannon Research Institute at The Children’s Hospital at TriStar Centennial in Nashville, Tennessee. It was published online in Blood Advances.

LIMITATIONS:

According to the authors, most PRO tools used in the study were not specifically developed for sickle cell disease, except for the Adult Sickle Cell Quality of Life Measurement Information System and PedsQL sickle cell disease module. The minimal clinically important differences were not disease-specific, as they were developed for other hematologic conditions. Additionally, PRO measures assessing pain had limitations in capturing information about pain events that occurred before exa-cel infusion or instances of chronic pain.

DISCLOSURES:

This study was designed by Vertex Pharmaceuticals Incorporated, in collaboration with academic authors. Akshay Sharma disclosed having relationships with CRISPR Therapeutics, Editas Medicine, Medexus Pharma, Inc., ReNagade Therapeutics, Sangamo Therapeutics, Spotlight Therapeutics, Vertex Pharmaceuticals, and Vindico Medical Education.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.