Kali Therapeutics, a clinical-stage biotechnology company focused on new therapies for autoimmune and inflammatory diseases, announced on Thursday that the US Food and Drug Administration (FDA) has cleared the company's Investigational New Drug (IND) application for KT501.

This clearance allows KT501 to advance into clinical evaluation in the United States.

According to Kali, KT501 is a first-in-class CD19xBCMAxCD3 tri-specific T-cell engager (TCE) being developed for a broad range of B cell–mediated autoimmune diseases. The novel, IgG-like tri-specific antibody binds CD19 and BCMA to reach a wide spectrum of B-cell populations, including plasma cells, while engaging CD3 through a proprietary masking design. This masking platform is intended to maximise potency and limit cytokine release, positioning KT501 to deliver deep, multi-targeted B-cell depletion with an improved safety margin.

The IND clearance is supported by the safety, tolerability, pharmacokinetic, and pharmacodynamic data emerging from KT501's ongoing first-in-human Phase 1a study in adults with rheumatoid arthritis, which is being conducted in Australia. KT501 is licensed to French healthcare company Sanofi S.A. (Euronext Paris:SAN) (Nasdaq:SNY) under a worldwide exclusive agreement announced in March 2026.