Mustang Bio announced the first subject treated with the optimized MB-106 (CD20-targeted, autologous CAR T cell therapy) manufacturing process, developed in collaboration between Mustang and Fred Hutchinson Cancer Research Center, has achieved a complete response (CR) at the lowest starting dose in an ongoing Phase 1/2 clinical trial. The trial is evaluating the safety and efficacy of MB-106 in subjects with relapsed or refractory B-cell non-Hodgkin lymphomas.
“We are thrilled to announce that we have achieved a complete response in the first subject dosed with MB-106 following Mustang and Fred Hutch’s enhancement to the cell process. MB-106 targets CD20, a commercially validated target on the surface of cancer cells that has lacked a strong CAR T-based clinical focus in the U.S. The complete response was seen on Day 28 in a subject with relapsed follicular lymphoma, and no cytokine release syndrome or neurologic toxicity were observed,” Manuel Litchman, M.D., President and Chief Executive Officer of Mustang, said. “The response was especially encouraging, since the subject received a dose of only 3.3 x 105 CAR T cells/kg. While this initial success of the optimized MB-106 is important, additional clinical testing is necessary. We are looking forward to follow-up data, as well as continuing to establish the safety of the therapy, which appears to be well tolerated to date. We are excited to work further with Fred Hutch to develop MB-106 and anticipate providing additional clinical results by year end.”
The Phase 1/2, open-label, dose-escalation trial is evaluating the maximum tolerated dose of MB-106. Secondary endpoints include safety and toxicity, preliminary antitumor activity as measured by overall response rate and complete remission rate, progression-free survival, and overall survival. Fred Hutch intends to enroll approximately 30 subjects on the trial, which is being led by principal investigator Mazyar Shadman, M.D., M.P.H., Assistant Member of Fred Hutch’s Clinical Research Division.
There are several forms of NHL, including follicular lymphoma, mantle cell lymphoma, marginal zone lymphoma, lymphoplasmacytic lymphoma and small lymphocytic lymphoma, which account collectively for about 45% of all cases of NHL. Most types of NHL are incurable with available therapies, except for allogenic hematopoietic stem cell transplant (allo-SCT). More than 70,000 new cases of B-cell NHL are diagnosed each year in the United States, and more than 19,000 patients die annually due to this group of diseases.
CD20 is a membrane-embedded surface molecule which plays a role in the differentiation of B-cells into plasma cells. The CAR T was developed by Mustang’s research partner, Fred Hutchinson Cancer Research Center, in the laboratory of Oliver Press, M.D., Ph.D., and Brian Till, M.D., in the Clinical Research Division and exclusively licensed to Mustang Bio in 2017. MB-106 has been optimized as a third-generation CAR derived from a fully human antibody and is currently in a Phase 1/2 open-label, dose-escalation trial at Fred Hutch in B-cell non-Hodgkin lymphoma patients.
