FDA slaps partial hold on bluebird bio's lovo-cel trial

Shares of bluebird bio (Nasdaq: BLUE) closed down 18% at $10.03 yesterday, after it announced that the US Food and Drug Administration has placed its clinical program for lovotibeglogene autotemcel (lovo-cel) - previously known as LentiGlobin - as a gene therapy for sickle cell disease (SCD) on partial clinical hold for patients under the age of 18.

The partial, temporary suspension relates to an ongoing investigation by bluebird bio into an adolescent patient with persistent, non-transfusion-dependent anemia following treatment with lovo-cel, now 18 months post-treatment. This patient is clinically well and there is no evidence of malignancy or clonal predominance. Enrollment and dosing for patients 18 and older living with SCD in the HGB-206, HGB-210 and LTF-307 clinical studies, as well as follow up for treated patients of all ages in all studies are continuing as planned.

In February this year, bluebird bio temporarily halted two trials, including a Phase III study, investigating its LentiGlobin gene therapy for sickle cell disease (SCD) after a suspected unexpected serious adverse reaction (SUSAR) of acute myeloid leukemia (AML).