By Alex Keown, BioSpace.com Breaking News Staff
CAMBRIDGE, Mass. – Shares of bluebird bio (BLUE) were up nearly 25 percent in after-hours trading after the company provided a sneak peek at its Phase I multiple myeloma treatment for patients who have not responded to previous treatments was an early success.
Data from the company’s investigational anti-BCMA CAR T cell product candidate, bb2121, co-developed by Celgene (CELG), is expected to be presented later today at the 28th EORTC-NCI-AACR Molecular Targets and Cancer Therapeutics Symposium in Munich. Celgene is the maker of the blockbuster blood cancer drug, Revlimid, as well as Pomalyst. This morning though, bluebird gave a peek into its research and announced that all patients in the second and third cohorts being dosed showed some positive responses. Two of the patients had no minimum residual disease – meaning that after one month of dosing, there was no sign of cancer.
The small Phase I trial of the CAR-T treatment dosed 11 patients in four separate dosing cohorts – each of which had gone through multiple rounds of treatments for the blood cancer before, but all to no avail. Nine of the patients in the small trial had already undergone their first multiple myeloma tumor restaging and were evaluable for efficacy, bluebird said. Of three patients who received the lowest dosing, bluebird said one patient showed at least a 50 percent reduction in signs of the cancer. The other six patients, all receiving higher doses, also showed at least a 50 percent reduction in signs of the disease, bluebird said.
The CAR-T treatment was also so far proving to be safe, with no dose-limiting toxicities and no Grade 3 or higher neurotoxicities or Grade 3 or higher cytokine release syndrome (CRS) having been observed, bluebird said. Toxicity will certainly be something that researchers and investors keep a close eye on in light of several deaths associated with another CAR-T therapy being developed by Juno Therapeutics. On Nov. 23, Juno halted its Phase II clinical Rocket trial of JCAR015 on hold for the second time following the announcement that two patients died. Those deaths marked the fourth and fifth deaths associated with this trial.
Patients received a conditioning regimen of cyclophosphamide and fludarabine, followed by an infusion of bb2121 anti-BCMA CAR T cells. The CAR T cells were produced from each patient’s own blood cells, which were modified using a lentiviral vector encoding the anti-BCMA CAR. The BCMA protein is seen as a promising target for multiple myeloma treatment. BCMA is estimated to be present in 60 to 70 percent of myeloma cases.
“In light of these positive data, and thanks to the multiple participating clinical sites and centralized manufacturing infrastructure we and our partner Celgene have built for this program, we anticipate efficiently completing the dose escalation stage of the trial and initiating the expansion cohort,” David Davidson, bluebird’s chief medical officer said in a statement.
While bluebird will present its data today, a group from the University of Pennsylvania will present Phase I data from its own CAR-T therapy for multiple myeloma next week at the American Society of Hematology meeting in San Diego. The Penn study also targets the same protein as the bluebird study, BCMA.