bluebird slips after latest LentiGlobin update

bluebird bio Inc. (NASDAQ:BLUE) lost $5.10 (11%) to $41.30 after reporting new results from three Phase I/II studies of LentiGlobin BB305 gene therapy, which the company is developing to treat sickle cell disease (SCD) and beta-thalassemia. The announcement came ahead of the company's planned presentations next month at the American Society of Hematology (ASH) meeting in San Diego. Abstracts from the conference were published Thursday morning.

An abstract for the HBG-206 study showed low vector copy numbers (VCN) in the peripheral blood of patients receiving LentiGlobin BB305 to treat SCD. The company said the low VCN likely contributed to low expression of anti-sickling hemoglobin...