bluebird bio Stock Plunges After Mixed Report on LentiGlobin Results at American Society of Hematology
Published: Dec 08, 2015
December 7, 2015
By Alex Keown, BioSpace.com Breaking News Staff
CAMBRIDGE, Mass. -- bluebird bio has plunged nearly 34 percent to $55.10 following the release of mixed data for its gene therapy sickle cell treatment revealed at the American Society of Hematology meeting in Orlando, Fla. this weekend.
The company announced its gene therapy treatment, LentiGlobin, works differently for each patient, which means single conclusive results cannot be achieved, Bidnessetc reported this morning. This was something hinted at in November when bluebird released preliminary information.
During its presentation at ASH, bluebird said two of the beta-thalassemia major patients using bluebird’s gene therapy LentiGlobin BB305, a treatment for blood disorders including beta- thalassemia major and sickle cell disease, have required transfusions. However, on a positive note, the company said at their most recent follow ups, three months and one month, respectively, “these patients were producing measurable levels of HbAT87Q.”
However, bluebird did show that some patients who required needed frequent and regular blood transfusions have responded positively to the therapy and have been transfusion free for up to two years.
This weekend’s report may have confirmed some investors’ fears after bluebird released preliminary information in November. Data released in November shows some of the patients treated with the therapy have not required blood transfusions in several months, something the patients typically underwent on a monthly basis. Likewise, in the spring, bluebird released a report showing a sickle cell patient has been transfusion free with no sickle cell hospitalizations for nearly three months after undergoing the therapy and he is now producing higher levels of hemoglobin. But, at least two of the three remaining beta-thalassemia patients have needed at least one transfusion and the third is still transfusion dependent, bluebird said in its data. The report indicates the gene therapy treatment is not something that is an effective treatment for every patient. The patients that have not shown as positive a response to the gene therapy treatment have two copies of a genetic mutation—each called b0—that prevents them from producing any beta globin, a subunit of hemoglobin. The patients show some response to the LentiGlobin treatment, and with some tweaks, perhaps patients with the b0/b0 mutation could show greater response.
Still, Nick Leschly, bluebird’s chief executive officer, told Adam Fuerstein of The Street that the mixed results should not cause a panic. He believes the patients will continue to improve with longer follow up so he's encouraged, Fuerstein reported.
Following the mixed results, stock analysts at thestreet rated bluebird’s stock a sell. Bluebird stock has been as high as $197.35 over the past 52 weeks.
“The company's weaknesses can be seen in multiple areas, such as its feeble growth in its earnings per share, deteriorating net income, disappointing return on equity and weak operating cash flow,” the analysis said.
In October, bluebird stock took a 6 percent hit after the company revealed a patient who underwent an early gene study treatment for beta-thalassemia seven years ago required new treatments following a relapse. Marina Cavazzana, a professor of hematology and lead investigator for bluebird’s HGB-205 clinical study, said the patient she treated in 2007 has required two blood transfusions after experiencing clinical symptoms of anemia.
LentiGlobin was granted Breakthrough Therapy Status by the U.S. Food and Drug Administration (FDA) in February. The designation is given to drugs expected to treat life-threatening illnesses in order to expedite the development and review of the drug.
Cambridge-based bluebird bio specializes in treatments for blood disorders and immuno-oncology through the use of gene therapy. In June, bluebird struck a deal with Kite Pharma, Inc. to develop T-cell therapies to treat cancer linked to Human papilloma virus (HPV). T-cell receptors are showing promise in boosting the body’s own immune system to combat cancer.