FDA Sounds Positive On Bluebird's One Gene Therapy But Doubts Another

The FDA signaled in briefing documents released that it may approve Bluebird bio Inc's BLUE beti-cel gene therapy to treat β-thalassemia for those who require regular blood transfusions.
The Prescription Drug User Fee Act (PDUFA) goal dates for beti-cel and eli-cel are August 19 and September 16.
Bluebird bio's blood disorder treatment demonstrates "clinically meaningful" benefit in patients, staff reviewers at the FDA said.
For eli-cel, the investigational gene therapy in development for early active cerebral adrenoleukodystrophy, the agency said its overall benefit-risk profile "is difficult to characterize because of the uncertain benefit and the uncertain magnitude of the risk of Myelodysplastic Syndrome (MDS)," a form of cancer that cropped up in three instances in bluebird's trial.
Related: Bluebird Bio Joins Layoff Band Wagon As Gene Therapy Biotech Cuts Staff To Reduce Costs.
"Three malignancies have been diagnosed among the 67 subjects treated with eli-cel, and it seems likely additional cases will emerge over time, driven by LVV integration into proto-oncogenes," FDA said.
The agency also noted that the cases of acute myeloid leukemia following treatment with a related LVV-based product in patients with sickle cell disease "also add to our concern."
A panel of FDA's outside experts is scheduled to discuss approval of the treatments later this week.
Price Action: BLUE shares are up 14.10% at $3.40 during the market session on the last check Tuesday.