Shares of gene therapies biotechnology company Bluebird Bio (BLUE) - Get Report dropped Tuesday premarket after the company announced the suspension of its Phase 1/2 and Phase 3 studies of its sickle cell therapy candidate.
The company suspended the studies due to a reported Suspected Unexpected Serious Adverse Reaction (SUSAR) of acute myeloid leukemia (AML).
"The safety of every patient who has participated in our studies or is treated with our gene therapies is the utmost priority for us," said CEO Nick Leschly. "We are committed to fully assessing these cases in partnership with the healthcare providers supporting our clinical studies and appropriate regulatory agencies. Our thoughts are with these patients and their families during this time."
Bluebird shares were down 27.6% to $33.12 premarket at the last check.
Bluebird placed the study on hold after receiving a report last week that a patient who was treated more than five years ago in a study was diagnosed with AML.
The company says it's investigating the cause of this patient's AML to determine whether there is any connection to his participation in the study.
Additionally, a second SUSAR of myelodysplastic syndrome in a patient was reported last week to the company and is currently being investigated.
In November, Bluebird said it would submit its application for the treatment, LentiGlobin, to the U.S. Food and Drug Administration for clearance in late 2022. The company had said earlier that the submission would come in the second half of 2021.
Bluebird Bio cited additional FDA requirements and challenges related to the coronavirus pandemic as reasons for the delay.