Press Release

June 11, 2021
1 min read

FDA lifts hold on trials of gene therapies for sickle cell disease, beta-thalassemia


Press Release

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The FDA lifted the clinical holds on four studies designed to evaluate two gene therapies for hematologic conditions.

The decision allows for resumption of the phase 1/phase 2 HGB-206 and phase 3 HGB-210 studies of bb1111 (LentiGlobin, bluebird bio) for adults and children with sickle cell disease, as well as the phase 3 Northstar-2 and Northstar-3 studies of betibeglogene autotemcel (bluebird bio) for treatment of adults, adolescents or children with transfusion-dependent beta-thalassemia.

Bluebird officials in February announced the suspension of clinical trials of LentiGlobin for sickle cell disease after reports that one patient treated more than 5 years ago in the HGB-206 trial was diagnosed with acute myeloid leukemia and another patient in the same study developed myelodysplastic syndrome.

The FDA subsequently placed a hold on trials of betibeglogene autotemcel, an autologous gene therapy that uses the same lentiviral vector (BB305) as LentiGlobin.

In March, bluebird bio reported it was very unlikely that the case of AML was related to the BB305 lentiviral vector. In April, bluebird officials announced a revised diagnosis for the reported myelodysplastic syndrome case, indicating the treating investigator determined the accurate diagnosis to be transfusion-dependent anemia.

“Patient safety continues to be our utmost priority, and we are grateful for the close partnership with the FDA, investigators, scientists and most importantly, patients, who all contributed to the assessments of the adverse events in HGB-206 that ultimately led to [this] announcement,” Andrew Obenshain, bluebird bio’s president of severe genetic diseases, said in a company-issued press release. “We remain committed to advancing the field through our learnings. Over the past 4 months, we have gained deeper knowledge and understanding of the pathophysiology of sickle cell disease that will allow us to better serve patients and the broader community. We look forward to resuming our clinical programs and continuing to advance toward major regulatory submissions for sickle cell disease and beta-thalassemia.”