A bluebird bio gene therapy for the rare blood disease beta thalassemia is now available Approved by the U.S. Food and Drug Administrationoffering a one-time treatment option that could eliminate the need for routine blood transfusions as the current standard of care for patients.
Somerville, Mass.-based Bluebird set a wholesale price of $2.8 million for the Zynteglo product, making it one of the most expensive treatments to hit the market. But the biotech company said Wednesday that it also proposed a reimbursement strategy related to patients benefiting from the treatment.
Beta thalassemia is an inherited blood disorder that causes low levels of hemoglobin, the oxygen-carrying protein in red blood cells. The resulting low levels of oxygen in the body can lead to dizziness, weakness, fatigue and bone problems, among other complications.
In the most severe forms of the disease, patients require regular life-long transfusions of red blood cells. Bluebird estimates that 1,300 to 1,500 people in the United States have transfusion-dependent beta thalassemia. While blood transfusions offer a treatment option, the process also poses other problems because it can lead to an excess buildup of iron in the organs. Medications are available to address iron overload, but these medications have their own side effects.
Zynteglo is made from a patient’s own stem cells. These cells are harvested from bone marrow and genetically modified in the laboratory to produce the functional components of hemoglobin. The engineered cells are then reinjected into the patient.
Bluebird tested Zynteglo in two single-arm, open-label Phase 3 studies that enrolled 41 patients. These participants, both children and adults, had beta thalassemia that required regular blood transfusions. The primary objective of the study was to demonstrate transfusion independence, defined as achieving and maintaining a predetermined hemoglobin level without any transfusion for at least 12 months. Of the 36 study participants who could be assessed, 89% achieved transfusion independence. The one-time treatment has also shown that its effects can be sustained. As of the last patient follow-up, results have been durable, according to Bluebird. The longest patient follow-up period was four years.
The most common adverse reactions associated with Zynteglo include decreased levels of platelets and other blood cells, mouth pain and inflammation, vomiting, fever, and hair loss. The FDA also noted that the therapy carries a risk of cancer, Concerns emerged last year in a separate test of Bluebird’s gene therapy for the different blood disease sickle cell disease. The cancer cases that suspend this clinical trial are Considered unlikely to be caused by gene therapy.
No cases of cancer have been reported in Zynteglo clinical trials. FDA advisory committee weighed Zynteglo’s cancer risk in June, then vote The consensus is that the benefits of this therapy outweigh its risks.The risk of blood cancer is drug label, but not in a black box, which is the FDA’s most severe type of warning. The prescribing information states that patients should be checked at least once a year for 15 years for any changes in their blood.
Bluebird said Zynteglo’s $2.8 million price tag reflects the potential efficacy of a one-time treatment that reduces the burden on patients and the healthcare system from regular blood transfusions. The company calculated that the financial burden could be as high as $6.4 million for a beta-thalassemia patient.
Considering financial relief, Bluebird announced a plan This limits the risk to the payer. This strategy allows payers to make advances that can be combined with outcome-based agreements. Under the agreement, Bluebird said it would reimburse Zynteglo up to 80% of the cost if a patient fails to achieve and maintain transfusion independence within two years of the gene therapy infusion. An estimated 70% to 75% of transfusion-dependent beta-thalassemia patients are covered by commercial insurance, Bluebird added, and the company is in talks with state pharmacy benefit managers who administer these plans. The company also spoke with state Medicaid agencies, which represent about 80 percent of publicly insured beta thalassemia patients.
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