FDA Approves New Gene Therapy Treatment for Rare Blood Disorder

The U.S. Food and Drug Administration (FDA) has given fast track approval through a pediatric disease voucher for Bluebird Bio’s Zynteglo, a treatment designed to tackle the rare condition known as transfusion-dependent beta-thalassemia (TDBT), a blood disorder that reduces hemoglobin and red blood cell counts in the bloodstream, leading to reduced oxygen delivery. Each dose is tailored to an individual’s genetic profile for maximum effectiveness.

TDBT is an inherited disease that significantly lowers life expectancy, with the average U.S. patient suffering from the condition dying at age 37. Bluebird estimates between 1,300 and 1,500 people in the U.S. suffer from the disease. Transfusion-dependent patients have to undergo red blood cell transfusions as frequently as every two weeks. According to Bluebird, clinical trials of Zynteglo resulted in 89 percent of patients achieving “transfusion independence,” defined as not needing a transfusion for at least 12 months.

But the price of Zynteglo, the most expensive drug in U.S. history, is $2.8 million. According to Bluebird, the price is a deal, since “the lifetime cost of medical care for a patient with transfusion-dependent beta-thalassemia can reach up to $6.4 million.”