bb21217 is a new treatment being investigated in myeloma that belongs to a type of immunotherapy known as chimeric antigen receptor T-cell (CAR-T) therapy. This involves T-cells being taken from the patient and being changed to find myeloma cells more easily. bb21217 is similar to its predecessor (bb2121) but this new construct includes a phosphoinositide 3-kinase inhibitor, whose addition is designed to make the cells more potent and enable them to persist longer.
December 02, 2018
Of the 12 patients who received treatment with bb21217, 83 percent (n=10) achieved an objective clinical response by IMWG criteria. As of the data extract, responses are ongoing in nine of 10 patients, including three with a complete response (CR) or stringent complete response (sCR), two with a very good partial response (VGPR) and four with a partial response (PR).
Evidence of myeloma in the bone marrow, known as minimal residual disease (MRD), was undetectable at a minimum of two time points, by next-generation sequencing at a sensitivity level of 10-5 or better in all responders who had evaluable bone marrow samples (n=4) with some as early as day 15.
CAR+ T cell expansion was observed during the first 30 days following treatment in all evaluable patients (n=11) with anti-BCMA CAR+T cells showing sustained persistence in all patients (3/3) with six or more months of follow-up.
The ongoing Phase 1 CRB-402 study is assessing a higher dose of 300 x106CAR+ T cells in both high and low tumor burden cohorts.