Cabaletta Bio Inc. (NASDAQ: CABA) presented clinical data showing that two of four patients with refractory pemphigus vulgaris achieved drug-free responses lasting six months after receiving the lowest dose of rese-cel without preconditioning treatment, according to presentations at the American Society of Gene & Cell Therapy 2026 Annual Meeting.

The Philadelphia-based biotechnology company reported that all four patients in the lowest dose cohort of its RESET-PV study showed initial improvement with reductions in disease activity scores as early as four weeks. The patients had baseline PDAI Total Activity scores ranging from 22 to 83 and completed at least 24 weeks of follow-up as of April 2, 2026.

The treatment demonstrated similar CAR T cell expansion patterns compared to patients who received preconditioning in other RESET trials. Three of the four patients experienced complete peripheral B cell depletion. One patient experienced grade 1 cytokine release syndrome, and no dose-limiting toxicities or neurotoxicity were observed.

"PC-free rese-cel has the potential to substantially expand access for patients in current CAR T centers on an outpatient basis as well as in community-based infusion centers," said David J. Chang, Chief Medical Officer of Cabaletta.

The company also presented manufacturing data from the first two autoimmune patients treated with rese-cel produced using Cellares' automated Cell Shuttle platform. Both patients completed at least four weeks of follow-up as of May 6, 2026. The automated manufacturing process met all release specifications with on-time delivery, and product quality metrics remained within established ranges.

Cabaletta expects higher-dose preconditioning-free data from RESET-PV in the second half of 2026 and initial data from RESET-SLE at the European Alliance of Associations for Rheumatology 2026 Congress in June.