As a potential blockbuster drug touted by Bristol Myers Squibb during its Celgene buyout, Reblozyl’s future success was in large part dependent on an approval for a group of bone marrow disorders called myelodysplastic syndromes (MDS). Now, it has that nod.
On Friday, Bristol Myers and partner Acceleron Pharma said the FDA has greenlighted Reblozyl to treat anemia in MDS patients with ring sideroblasts, a low-risk subtype of the blood cancer in which red blood cells contain a ring of excess iron.
The approval is limited to those who require regular red blood cell transfusion and have failed an erythropoiesis-stimulating agent such as Amgen and Johnson & Johnson’s Epogen/Procrit.
MDS marks the second indication for the anemia drug after its initial nod for patients with beta-thalassemia in November. Back then, Jefferies analysts tied about two-thirds of the drug’s $2 billion peak sales estimate to MDS.
That's no surprise; MDS is a much larger market than beta-thalassemia. According to Acceleron CEO Habib Dable, the company estimates there are more than 20,000 patients with lower-risk MDS-RS who would be eligible to receive Reblozyl, he said on a conference call in February. In contrast, the U.S. beta-thalassemia population numbers only 1,000 to 1,500 patients. And let’s not forget Bluebird Bio’s gene therapy Zynteglo, which is already approved in Europe for beta-thalassemia, potentially eliminating the need for Reblozyl treatment—though its filing discussions with the FDA have hit some hurdles.
The FDA based its latest Reblozyl decision on data from the phase 3 Medalist trial. In the study, 38% of patients who got Reblozyl achieved transfusion independence for at least two months during the first 24 weeks of the study, significantly more than the 13% investigators observed in the placebo group. The study also met the key secondary endpoint of blood transfusion freedom for 12 or more weeks. What’s more, Reblozyl-related adverse events such as fatigue and asthenia also decreased over time.
Reblozyl was among five drugs in Celgene’s late-stage pipeline that it said could potentially reach blockbuster status. The other four are JAK inhibitor Inrebic, which the FDA cleared for myelofibrosis in August; just-approved multiple sclerosis drug Zeposia; as well as forthcoming CAR-T therapies liso-cel and ide-cel.
During the fourth-quarter conference call with investors in February, Acceleron chief commercial officer Sujay Kango declined to offer any initial sales numbers regarding Reblozyl. But he said the drug has “very good coverage” and it’s not seeing any kind of payer pushback.
The company did acknowledge problems with prior authorization but stressed the hurdles were anticipated as part of the process. It expects the situation to continue as Bristol has filed to get a permanent J code from CMS, which will streamline the reimbursement process. The company’s hopeful it could get it sometime later this year or early in 2021.