Affinia Therapeutics Secures FDA IND Clearance for AAV Gene Therapy AFTX-201 in BAG3 Dilated Cardiomyopathy

WALTHAM, Mass., Feb. 4, 2026 — Affinia Therapeutics announced that the U.S. Food and Drug Administration (FDA) has accepted its Investigational New Drug (IND) application for AFTX-201, an investigational adeno-associated virus (AAV) gene therapy being developed for the treatment of BAG3-associated dilated cardiomyopathy (DCM), a rare and severe inherited heart disease with limited therapeutic options.

AFTX-201 is designed to deliver a fully human, full-length functional BAG3 transgene using Affinia’s proprietary engineered AAV capsid, which enables highly efficient cardiac transduction at doses that are five- to ten-fold lower than those required for conventional AAV capsids such as AAV9 or AAVrh74. The therapy is intended to be administered as a one-time intravenous AAV infusion, with the goal of restoring BAG3 protein expression and improving cardiac function.

The IND clearance enables Affinia to initiate the UPBEAT© Phase 1/2 clinical trial in the first half of 2026. The multicenter, open-label study will evaluate the safety, tolerability, pharmacodynamics, and preliminary efficacy of AFTX-201 in adults with genetically confirmed BAG3 DCM. The trial includes a dose-exploration phase followed by dose expansion, with safety assessed through 52 weeks post-administration.

Preclinical studies supporting the IND demonstrated robust and durable BAG3 protein expression in the heart following AAV delivery, resulting in complete restoration of cardiac function in an animal model of BAG3 DCM. These findings suggest that AFTX-201 has the potential to address the underlying genetic cause of disease rather than providing symptomatic relief.

BAG3 DCM affects tens of thousands of patients across North America and Europe and is characterized by early-onset heart failure and rapid disease progression. Despite existing standard-of-care therapies, approximately 25% of patients ultimately require heart transplantation, underscoring the significant unmet medical need and the potential impact of a disease-modifying AAV gene therapy approach.