Cabaletta Bio, Inc.

Cabaletta Bio, Inc. is a late clinical-stage biotechnology company that discovers and develops engineered T cell therapies for autoimmune diseases. The company's proprietary CABA®, or Cabaletta Approach to B cell Ablation platform, utilizes the CARTA (Chimeric Antigen Receptor T cells for Autoimmunity) approach to potentially reset the immune system. This platform aims to enable complete and durable responses for a broad range of autoimmune diseases and has potential applicability across dozens of identified, evaluated, and prioritized autoimmune diseases. The company's lead product candidate within the CARTA strategy is Resecabtagene autoleucel, or rese-cel (formerly CABA-201). Rese-cel is a 4-1BB co-stimulatory domain-containing fully human CD19-CAR T construct designed to treat a broad range of autoimmune diseases. It is engineered to achieve transient and deep depletion of all B cells following a single, weight-based infusion of T cells. This process allows for the deep elimination of all disease-contributing B cells, followed by repopulation with healthy transitional, naïve B cells, potentially resetting the immune system and leading to clinical responses without chronic therapy. The efficacy and safety of rese-cel were reviewed in a February 2026 Nature Biotechnology publication. In December 2025, the company initiated a registrational trial for rese-cel in patients with dermatomyositis or anti-synthetase syndrome.