According to a story from EurekAlert!, the biopharmaceutical company Celgene Corporation and the gene therapy company bluebird bio, inc. recently announced that the interim results for a Phase 1 clinical trial have recently been published in the New England Journal of Medicine. This trial is testing bb2121, an experimental chimeric antigen receptor (CAR) T-cell therapy that is being developed by the two companies. The therapy was tested as a treatment for relapsed, refractory multiple myeloma, a cancer that affects plasma cells.
About Multiple Myeloma
Multiple myeloma, which is occasionally referred to as plasma cell myeloma, is a blood cancer that affects plasma cells. These are white blood cells that produce antibodies. The overall cause of multiple myeloma is not well understood, however, some risk factors have been identified. These include obesity, family history, smoldering myeloma, and monoclonal gammopathy of undetermined significance. These last two conditions have the potential to develop into multiple myeloma. Symptoms of this cancer include bone pain, infections, anemia, kidney failure, overly thick blood, confusion, fatigue, headaches, and amyloidosis. Treatment includes chemo, stem cell transplant, and other medications for relapsed disease, which is common. Five year survival rate is 49 percent in the US. To learn more about multiple myeloma, click here.
About The Trial
The interim results suggest a therapy with real treatment potential, but adverse events in the study were frequent. Neutropenia, a condition of reduced white blood cell count, occurred in 85 percent of the patients, and other blood toxicities appeared as well. Neurotoxicity also appeared in 42 percent of the multiple myeloma patients. Infection also occurred in 42 percent of patients, and cytokine release syndrome, a side effect well known in CAR-T cell therapies that can cause severe symptoms, appeared in 76 percent of patients.
These results suggest that patients using bb2121 should expect the onset of serious side effects. However, the treatment also achieved an objective response rate of 85 percent with 45 percent of the participants achieving a complete response. A test of 16 multiple myeloma patients that responded well to the therapy for minimal change disease, an indicator that can predict relapse, saw all of them test negative at at least one point in time.
While the side effects for bb2121 appear significant, the efficacy results cannot be ignored, and suggest that this investigational CAR-T cell therapy could be useful treatment for patients with severe multiple myeloma.