CAR T-Cell Therapy Nearly Eliminates Tumors in All Relapsed or Refractory Myeloma Patients in Phase 1 Trial

Updated results from an ongoing Phase 1 clinical study of bb2121, an investigational therapy for the treatment of multiple myeloma, show that 100% of patients responded to active doses of the treatment, Bluebird bio and Celgene Corporation announced.

The findings were recently presented at the American Society of Clinical Oncology (ASCO) 2017 Annual Meeting, in Chicago. The poster, “First-in-human multicenter study of bb2121 anti-BCMA CAR T-cell therapy for relapsed/refractory multiple myeloma: Updated results,” was presented by Jesus Berdeja, MD, from the Sarah Cannon Research Institute and Tennessee Oncology, Nashville.

The trial, (NCT02658929), is a dose–escalation study of bb2121, an anti-BCMA chimeric antigen receptor (CAR) T-cell therapy for the treatment of relapsed/refractory multiple myeloma.

The study has so far enrolled 21 patients to assess bb2121’s safety and effectiveness, as well as to find the effective dose for the upcoming Phase 2 clinical trial.

Primary endpoints include the incidence of adverse events and abnormal laboratory test results, including dose–limiting toxicities. The study will also assess therapy response rates as complete response, very good partial response, or partial response.

Patients enrolled in the study tended to be heavily pre–treated with a median of seven prior medication therapies attempted. Prior to receiving bb2121, patients were treated with a conditioning regimen of cyclophosphamide and Fludara (fludarabine).

Initial results from the study show that 100% of patients in the active dose cohort (patients who received more than 50 million cells) achieved an active response to the treatment. Nearly three-quarters of patients (73%) in the active dose cohort were noted to have a very good partial response or better. Additionally, as of May 4, 2017, no disease progression had been noted in the active dose cohort. The study found no dose–limiting toxicities.

“The heavily pretreated, relapsed/refractory patients in this study have few effective treatment options, highlighting the importance of this interim data. All patients previously underwent autologous HSCT, and received a median of 7 lines of prior therapy,” Michael Pehl, president of hematology and oncology at Celgene, said in a press release. “The consistency, depth and durability of these patients’ responses coupled with a manageable safety profile is very exciting, and we believe will provide hope for patients in this setting. Efforts are underway to advance the development of bb2121 for patients with relapsed/refractory multiple myeloma.”

Researchers anticipate enrollment of up to 50 patients in the current study with an upcoming Phase 2 clinical trial also planned.