FDA approves Zynteglo for patients with beta-thalassemia needing regular blood transfusions

Zynteglo (betibeglogeneautotemcel; Bluebird Bio) was recently approved by the US Food and Drug Administration (FDA). The cell-based therapy is now approved to treat adults and children afflicted with beta-thalassemia in need of a regular red blood cell transfusion.

Beta-thalassemia is a blood disorder where mutations take place in the beta-globin subunit reducing the normal hemoglobin and red blood cells in the bloodstream, which lowers the amount of oxygen in the body to dangerous levels. 

Symptoms include fatigue, dizziness, weakness, and blood abnormalities, but more serious complications can arise. Lifelong red blood cell treatment is often needed in the most serious cases referred to as transfusion-dependent beta-thalassemia, but the treatment can lead to complications in organs such as the heart and liver. 

Zynteglo has been established as a safe and effective treatment through 2 multicenter clinical studies, which included adults and children in need of regular transfusions because of beta-thalassemia. Transfusion independence was achieved in 89% of patients, where a pre-determined level of hemoglobin was in the blood for at least 12 months without any red blood cell transfusions.

The FDA listed the following side effects for Zynteglo on their website: reduced platelet and other blood cell levels, as well as mucositis, febrile neutropenia, vomiting, pyrexia (fever), alopecia (hair loss), epistaxis (nosebleed), abdominal pain, musculoskeletal pain, cough, headache, diarrhea, rash, constipation, nausea, decreased appetite, pigmentation disorder, and pruritus (itch).

Risk of blood cancer was mentioned, but there have been no cases of such recorded yet. The FDA encouraged patients who receive Zynteglo to have their blood monitored for cancer every 15 years, and to be monitored for hypersensitive reactions, bleeding, and thrombocytopenia during treatment.

Along with being approved by the FDA, Zynteglo was granted a rare pediatric disease voucher, and was given Orphan, Priority Review, Breakthrough Therapy, and Fast Track designations.

“Today’s approval is an important advance in the treatment of beta-thalassemia, particularly in individuals who require ongoing red blood cell transfusions,” said Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research. “Given the potential health complications associated with this serious disease, this action highlights the FDA’s continued commitment to supporting development of innovative therapies for patients who have limited treatment options.”

Reference

FDA approves firstcell-based gene therapy to treat adult and pediatric patients with beta-thalassemia who require regular blood transfusions. U.S. Food and Drug Administration. August 17, 2022. Accessed August 17, 2022. https://www.fda.gov/news-events/press-announcements/fda-approves-first-cell-based-gene-therapy-treat-adult-and-pediatric-patients-beta-thalassemia-who?utm_medium=email&utm_source=govdelivery