Vertex shares new Casgevy data, including first-ever results in children

Vertex Pharmaceuticals announced data from multiple studies demonstrating the clinical benefits of Casgevy, an approved CRISPR/Cas9 gene-editing therapy, in people ages 5 years and older living with severe sickle cell disease (SCD) or transfusion-dependent beta thalassemia (TDT).

The results, including the first presentation of clinical data from pivotal studies in children ages 5-11 years, and longer-term data from the pivotal studies of people with severe SCD and TDT ages 12 years and older, will be presented at the American Society of Hematology (ASH) Annual Meeting.

In children ages 5-11 with SCD, 11 patients have been dosed with Casgevy in the phase 3 CLIMB-151 clinical study, and all (4/4) patients with sufficient follow-up achieved the primary endpoint of being free from vaso-occlusive crises (VOCs) for at least 12 consecutive months. No patient experienced a VOC following infusion with Casgevy, with the longest duration of VOC-free of approximately two years.

In children ages 5-11 with TDT, 13 patients have been dosed with Casgevy in the phase 3 CLIMB-141 clinical study, and all (6/6) patients with sufficient follow-up achieved the primary endpoint of transfusion independence for at least 12 consecutive months while maintaining a weighted average hemoglobin (Hb) of at least 9 g/dL (TI12). Following Casgevy infusion, 12/13 are transfusion free, with the longest duration of transfusion free just under two years.

“With dosing completed in the 5-11 age group and the Commissioner’s National Priority Voucher for Casgevy in this population in hand, we are excited to begin global regulatory filings in the first half of next year and bring this potentially transformative therapy to eligible children as soon as possible,” said Carmen Bozic, MD, chief medical officer at Vertex.

Casgevy, co-developed with CRISPR Therapeutics, was approved by the U.S. FDA in December 2023, as the first gene-edited cell therapy for patients with sickle cell disease. In early 2024, its approval was expanded to include the treatment of transfusion-dependent beta thalassemia in patients 12 years and older.