New data from an ongoing open-label Phase 1/2 clinical trial, HGB-206, evaluating bluebird bio’s (NASDAQ:BLUE) LentiGlobin gene therapy in sickle cell disease (SCD) patients showed a significant treatment benefit. The results were presented at ASH in Orlando.
Participants in Group C (17 treated thus far) continue to produce high levels of gene therapy-derived anti-sickling hemoglobin, HbAT87Q, accounting for at least 40% of total hemoglobin in those with six or more months of follow-up. Cherry-picking the data, nine patients with at least six months of follow-up who had at least four vaso-occlusive crisis (VOC) or acute chest syndrome (ACS) events in the prior two years experienced a 99% reduction in annualized rate of VOC and ACS with no reports of such events up to 21 months post-infusion.
At data cutoff, 78% (n=7/9) of patients in Groups A & B had not required red blood cell transfusions post treatment.
No new safety signals were observed.
LentiGlobin is designed to add functional copies of a modified form of the β-globin gene (βA-T87Q-globin gene) into a patient’s own hematopoietic (blood) stem cells. Once patients have the βA-T87Q-globin gene, their red blood cells can produce anti-sickling hemoglobin which decreases the proportion of sickled hemoglobin and lessens SCD complications.
A long-term follow-up study, LTF-303, in SCD is ongoing with an estimated completion date of March 2031.
A Phase 3 trial, HGB-210, should commence next quarter.