- Bluebird Bio stock sank 6.5% Monday after after the company said a patient with the blood disorder beta-thalassemia, who treated with a first-generation version of Bluebird's gene therapy, had a relapse after more than seven years. Although the stock recovered a bit afterwards, Bluebird shares have fallen more than 50% in the last three months.
- The patient was treated with the first-gen gene therapy HPV569 in 2007, with the goal of having the patient's body produce functional hemoglobin.
- Since the patient was treated, Bluebird has developed a more potent version of the therapy.
Bluebird has been in the process of developing and refining a gene therapy to treat patients with beta-thalassemia and sickle cell anemia, with some positive early results, but the latest news caused some shakiness among shareholders.
There are many reasons to not panic over the latest news. The company made a point to explain that the patient has been on the brink of needing a blood transfusion for some time. In addition, there is a significant difference between the ability of the old therapy and the new therapy (BB305) to produce functional hemoglobin.
The company will continue to communicate about the new, more potent therapy and will be presenting at the American Society of Hemoglobin annual meeting in December.