Bispecific Antibody in Phase 1 Multiple Myeloma Trial Named Orphan Drug by FDA, Teneobio Announces

The U.S. Food and Drug Administration (FDA) has granted orphan drug status to Teneobio‘s bispecific antibody TNB-383B as a possible treatment of multiple myeloma.

Orphan drug designation provides Teneobio with benefits, including financial incentives for therapy development and commercialization, should it be approved. It also provides U.S. market exclusivity for seven years upon approval, FDA support for clinical studies, and special fee exemptions and reductions.

TNB-383B is an engineered antibody that acts as a bridge between immune cells and cancer cells by binding to proteins on the surface of both cell types. Specifically, the antibody binds to the CD3 surface receptor on the immune T-cells, and to the B-cell maturation antigen (BCMA) on myeloma cells.

By bringing T-cells closer to cancer cells, TNB-383B aims to promote cancer cell death while reducing the release of specific signaling molecules (known as cytokines) from activated T-cells — a process that causes most side effects in immunotherapy use.

Preclinical studies in mouse models of myeloma found treatment with TNB-383B prevented tumor growth, eliminated myeloma cells, and led to a lower production of inflammatory molecules compared to other two-target antibodies, the reason it is believed to carry fewer side effects.

TNB-383B use in bone marrow samples from relapsed multiple myeloma patients also showed a dose-dependent activation of T-cells and cancer cell death.

A Phase 1 trial (NCT03933735) is currently testing TNB-383B in advanced multiple myeloma patients previously given a minimum of three prior therapies. The study’s first part in 24 patients will test increasing doses of TNB-383B, delivered into the bloodstream every three weeks, to identify an optimal dose.

An additional 48 patients will then be enrolled and treated at that optimal dose to evaluate safety and preliminary signs of efficacy, as well as the therapy’s pharmacokinetics and pharmacodynamics — how the medicine acts and is processed in the body. The trial is enrolling patients at its U.S. site; information can be found here.

“New and better treatment options are needed for multiple myeloma. While there are a number of BCMA-targeting agents currently in clinical development, TNB-383B … is a bispecific comprised of a unique T-cell engager designed to maximize the therapeutic window for this class of drugs,” Roland Buelow, chief executive officer of Teneobio, said in a press release.

Under a collaboration agreement between AbbVie, Teneobio, and its affiliate TeneoOne that is leading TNB-383B through early clinical studies, AbbVie may upon their completion acquire TeneoOne and proceed with TNB-383B’s global development and commercialization.