Gene therapy by Vertex demonstrates potential in treating blood disorders in children

Vertex Pharmaceuticals reported that its gene therapy demonstrated promising outcomes in children aged 5 to 11 suffering from sickle cell disease, enabling them to remain free from painful episodes. Additionally, children with another blood disorder requiring frequent transfusions were able to stay transfusion-free for at least a year.

This advancement highlights the therapy's potential to treat younger patients and could broaden the use of Casgevy, currently approved for patients 12 years and older with sickle cell disease or transfusion-dependent beta thalassemia (TDT).

Vertexs Chief Medical Officer, Carmen Bozic, noted that this is the first clinical data ever shared for a genetic therapy in children aged 5-11 with sickle cell disease, emphasizing Casgevys transformative possibilities.

Casgevy employs CRISPR gene-editing technology, which acts like molecular scissors to remove faulty sections of genes and replace them with normal DNA. Vertex plans to submit applications to global regulators in the first half of next year and has received a National Priority Voucher for the 5-11 age group, which will expedite regulatory review.

In a late-stage clinical trial, four children with sickle cell disease who received Casgevy experienced no vaso-occlusive crises for at least 12 consecutive months, with the longest period reaching nearly two years. These crises, caused by blockages from sickled red blood cells, lead to severe pain and are a defining feature of the disorder.

Among 12 patients with TDT treated with Casgevy, all remained transfusion-free, with the longest interval just under two years. One patient with TDT passed away due to complications from a pre-transplant chemotherapy regimen, which included the drug busulfan, causing severe liver-related veno-occlusive disease.

The results were presented at the American Society of Hematology Annual Meeting.

Author: Ava Mitchell