March Biosciences Begins Phase 2 Trial for MB-105 CAR-T Therapy in T-Cell Lymphoma

In a notable advancement for cancer treatment, March Biosciences has announced the commencement of dosing in its Phase 2 clinical trial for MB-105, a pioneering CD5-targeted CAR-T cell therapy. This innovative treatment is designed for patients suffering from relapsed or refractory CD5-positive T-cell lymphoma, a condition with very limited existing treatment options. Sarah Hein, the Co-Founder and Chief Executive Officer of the company, highlighted the significance of this milestone, emphasizing the potential of MB-105 to address critical needs for patients with T-cell lymphomas, a category of cancers that have not benefited as much from CAR-T therapies as B-cell lymphomas have.

The ongoing Phase 2 clinical trial is structured as a multi-center, single-arm, two-stage, open-label study. Its primary aim is to investigate both the safety and efficacy of MB-105 in treating patients with relapsed or refractory CD5-positive T-cell lymphoma. The study is set to enroll approximately 46 patients and will be conducted at leading cancer centers across the United States. The first patient was dosed at The University of Texas MD Anderson Cancer Center, under the leadership of Dr. Swaminathan P. Iyer, a professor in the Department of Lymphoma/Myeloma at MD Anderson.

This trial builds on encouraging results from a previous Phase 1 study, where MB-105 showed a promising safety profile and achieved durable remissions in patients who had been heavily pretreated. Impressively, CD5 CAR-T cells were successfully produced in 93% of manufacturing attempts. The therapy demonstrated a manageable safety profile, with no severe cytokine release syndrome or neurologic events occurring. The novel CAR design of MB-105 targets malignant cells specifically, avoiding damage to normal T-cells.

Further details about the trial, which is currently enrolling participants, can be accessed on the ClinicalTrials.gov website under the identifier NCT06534060.

The advancement of MB-105 follows a successful Series A financing round in October 2024, led by Mission BioCapital and 4BIO Capital, with additional investment from KdT Ventures, Alexandria Venture Investments, Volnay Therapeutics, Modi Ventures, and Mansueto Investments. Existing stakeholders such as TMC Venture Fund, Cancer Focus Fund, Small Ventures, and Portal Innovations also contributed to the funding. This financial boost has enabled March Biosciences to make significant strides in clinical and regulatory areas, including receiving the FDA orphan drug designation for MB-105 in January 2025. This designation offers various development incentives and could grant seven years of market exclusivity upon FDA approval.

MB-105 is touted as a first-in-class, autologous CD5-targeted CAR-T cell therapy and carries the orphan-drug designation. It is under development for CD5-positive hematologic malignancies, encompassing T-cell lymphoma, T-cell acute lymphoblastic leukemia, chronic lymphocytic leukemia, and mantle cell lymphoma. The therapy's proprietary CAR design is engineered to selectively attack malignant cells, preserving the function of normal T-cells. The ongoing Phase 2 trial is a crucial step in evaluating MB-105 for patients with relapsed or refractory T-cell lymphoma.

Houston-based March Biosciences was established from the Center for Cell and Gene Therapy at Baylor College of Medicine, Houston Methodist Hospital, and Texas Children’s Hospital. The company is particularly focused on tackling cancers that are resistant to current immunotherapies. To date, March Biosciences has raised over $52 million through venture financing, and support from the Cancer Prevention & Research Institute of Texas and the NIH SBIR program.