FDA approves gene therapies for the treatment of sickle cell disease
The U.S. Food and Drug Administration has approved Casgevy (exagamglogene autotemcel [exa-cel]), a CRISPR/Cas9 genome-edited cell therapy, for the treatment of sickle cell disease (SCD) in patients 12 years and older with recurrent vaso-occlusive crises (VOCs), according to a press release. The FDA also approved Lyfgenia, a cell-based gene therapy which uses a lentiviral vector for genetic modification, for the treatment of patients 12 years of age and older with sickle cell disease and a history of vaso-occlusive events (VOEs).
“Sickle cell disease is a rare, debilitating and life-threatening blood disorder with significant unmet need, and we are excited to advance the field especially for individuals whose lives have been severely disrupted by the disease by approving 2 cell-based gene therapies today,” said Nicole Verdun, MD, director of the Office of Therapeutic Products within the FDA’s Center for Biologics Evaluation and Research. “Gene therapy holds the promise of delivering more targeted and effective treatments, especially for individuals with rare diseases where the current treatment options are limited.”
Approval of Casgevy was based on an ongoing single-arm, multi-center trial involving adult and adolescent patients with SCD and a history of at least 2 severe VOCs in the previous 2 years. The primary outcome focused on achieving freedom from severe VOC episodes for at least 12 consecutive months during a 24-month follow-up period. Out of 44 treated patients, 29 (93.5%) met this criterion, demonstrating successful engraftment without graft failure or rejection. Common side effects included low platelet and white blood cell levels, mouth sores, nausea, musculoskeletal pain, abdominal pain, vomiting, febrile neutropenia, headache, and itching.
Approval of Lyfgenia was based on a 24-month multicenter study involving patients with SCD aged 12 to 50 with a history of VOEs. The primary effectiveness measure was the complete resolution of VOEs (VOE-CR) between 6 and 18 months post-infusion, with 88% of patients achieving this outcome. Common side effects included stomatitis, low platelet, white blood cell, and red blood cell levels, as well as febrile neutropenia, consistent with chemotherapy and the underlying disease. Notably, Lyfgenia carries a black box warning due to cases of hematologic malignancy (blood cancer) in treated patients.
Read the full press release here.