bluebird bio Inc. (NASDAQ:BLUE) reported updated data from the Phase I CRB-401 trial evaluating its chimeric antigen receptor (CAR) T cell therapy bb2121 in patients with relapsed or refractory multiple myeloma. The data were presented Friday at the American Society of Clinical Oncology (ASCO) meeting in Chicago.
Among 18 patients in the dose-escalation portion who received an active dose of bb2121 (≥150x10^6 CAR T cells), median progression-free survival (PFS) was 11.8 months vs. 2.7 months in patients who received a lower inactive dose of bb2121. Among 16 patients who were negative for minimal residual disease (MRD), median PFS was 17.7 months.
Patients in the dose-escalation portion (n=21) had a median of seven prior treatment regimens and received one of four dose levels of bb2121 ranging from 50x10^6 to 800x10^6 CAR T cells. The trial also included a dose-expansion portion of 22 patients with a median of eight prior treatment regimens who received bb2121 at a dose range of 150-450x10^6 CAR T cells.
Overall, 63% of the 43 patients treated across all dose cohorts experienced cytokine release syndrome (CRS), which bluebird said were mostly low grade and manageable cases.
bluebird reported response data from the trial at last year's American Society of Hematology (ASH) meeting in Atlanta (see BioCentury Extra, Dec. 11, 2017).
bluebird Senior Director of Clinical Development Travis Quigley told BioCentury the company plans to start a Phase III trial of bb2121 this year as a third-line treatment of MM.
Celgene Corp. (NASDAQ:CELG), which holds exclusive, worldwide rights to bb2121 from bluebird, is evaluating the candidate in the pivotal Phase II KarMMa trial to treat relapsed and refractory MM.
bb2121 comprises autologous T cells transduced ex vivo with an anti-BCMA02 CAR lentiviral vector delivering the CAR targeted to tumor necrosis factor (TNF) receptor superfamily member 17 (BCMA; TNFRSF17; CD269). The product has breakthrough therapy designation from FDA and PRiority MEdicines (PRIME) designation from EMA.