First Patient with CD5-Positive T-Cell Lymphoma Dosed with MB-105

The first patient with relapsed or refractory CD5-positive T-cell lymphoma has been dosed in a phase 2 clinical trial evaluating the CD5-targeted CAR-T cell therapy MB-105, it has been announced.

The milestone was noted in a news release issued by clinical stage biotechnology company March Biosciences.

“This represents a significant milestone in advancing MB-105 as a potential treatment option for patients with T-cell lymphoma who currently face extremely limited therapeutic choices,” said Sarah Hein, co-founder and CEO of March Biosciences, in the news release. “CAR-T therapies have revolutionized the treatment of B-cell lymphomas and leukemias but have not successfully addressed the rarer T-cell lymphomas and leukemias. We are optimistic that this larger trial will further validate MB-105's potential to address the critical unmet needs of these patients and look forward to reporting our first clinical readouts.”

The multi-center, single-arm, two-stage, open-label study is set to evaluate the safety and efficacy of MB-105, and it will enroll approximately 46 patients across both of its stages. The study’s first patient was dosed at The University of Texas MD Anderson Cancer Center in Houston, and the trial is led by Dr. Swaminathan P. Iyer, a professor in the Department of Lymphoma/Myeloma at MD Anderson, as detailed in the news release.

The trial is currently recruiting participants, according to its listing on clinicaltrials.gov. It has an estimated primary completion date of February 2028, and a study completion date of December 2029, according to the listing.

Prior phase 1 trial results in T-cell lymphoma, the news release noted, had shown that treatment with MB-105 had resulted in a favorable safety profile and durable remissions among heavily pretreated patients.

Earlier this year, March Biosciences announced that MC-105 had received orphan drug designation from the U.S. Food and Drug Administration (FDA). Orphan drug designation, as explained by the FDA on its website, is granted by the regulatory agency to a drug or biological product intended to prevent, diagnose or treat a rare disease or condition, and the designation qualifies sponsors for incentives such as tax credits for qualified clinical trials, exemption from user fees and potentially seven years of market exclusivity after approval.

“Beyond an important regulatory milestone, securing orphan drug designation for MB-105 from the FDA underscores the critical need for new therapeutic options for patients with T-cell lymphoma,” said Hein said in a news release issued at the time of the orphan drug designation. “Currently, patients with treatment-resistant or recurrent T-cell cancers face an extremely poor prognosis. The MB-105 phase 1 trial has shown promising safety and efficacy signals in relapsed/refractory T-cell lymphoma patients. This designation further validates our development strategy as we prepare to initiate our phase 2 clinical trial in early 2025.”

CAR-T cell therapy, as defined by the National Cancer Institute on its website, involves a patient’s T cells, a type of immune cell, being taken from a patient’s blood, changed in a laboratory so that they will attack cancer cells, grown in a laboratory and given back to a patient by infusion.

MB-105, according to the news release, is in development for CD5-positive hematologic malignancies including T-cell lymphoma, T-cell acute lymphoblastic leukemia, chronic lymphocytic leukemia and mantle cell lymphoma.

T-cell lymphomas, as the American Cancer Society explained on its website, make up less than 15% of non-Hodgkin lymphomas in the United States, and are lymphomas that start in early forms of T lymphocytes, a type of white blood cell that is part of the immune system.

For more news on cancer updates, research and education, don’t forget to subscribe to CURE®’s newsletters here.