CABA

EX-99.1

2 caba-ex99_1.htm

EX-99.1

EX-99.1

Exhibit 99.1

Cabaletta Bio Reports Second Quarter 2026 Financial Results and Provides Business Update

Registrational RESET-Myositis® clinical data on track to be reported in mid-2027 to support 2H27 BLA submission for rese-cel

Juvenile myositis Phase 1/2 data expected to be submitted with BLA to support potential FDA Priority Review Voucher

Registrational RESET-SSc® enrollment in approximately 25 patients with SSc-associated interstitial lung disease anticipated to initiate in 4Q26

PC-free approach being incorporated in RESET-MG® based on emerging insights from PC-free RESET-SLE® and RESET-PV® cohorts and previously reported Phase 1/2 clinical data

Pursuing expansion of outpatient dosing option for rese-cel within the RESET™ clinical development program based in part on favorable safety data reported at EULAR 2026

ElevateBio selected as second CDMO for clinical and commercial manufacturing of rese-cel

PHILADELPHIA, Aug. 13, 2026 (GLOBE NEWSWIRE) -- Cabaletta Bio, Inc. (Nasdaq: CABA), a late-stage clinical biotechnology company focused on developing and launching curative targeted cell therapies designed specifically for patients with autoimmune diseases, today reported financial results for the second quarter ended June 30, 2026, and provided a business update.

“A single infusion of rese-cel has demonstrated the potential to deliver deep, clinical responses after discontinuation of all immunomodulators with up to 1.5 years of follow-up as reported in the most recent Phase 1/2 clinical experience. Continued expansion of the outpatient dosing option with rese-cel remains a top priority, and we believe the reported safety profile supports its incorporation across the RESET clinical development program,” said Steven Nichtberger, M.D., Chief Executive Officer of Cabaletta. “Additionally, we view the product design and development characteristics of rese-cel, including the use of a fully-human CAR construct, weight-based dosing, and a well-characterized manufacturing process, to have contributed to the compelling clinical outcomes reported in adult and juvenile patients across multiple autoimmune diseases. As we progress rese-cel through and into registrational trials for myositis and systemic sclerosis, respectively, we are also particularly encouraged by the reported PC-free data in lupus and PV patients which have prompted us to incorporate the PC-free approach in RESET-MG.”

Recent Operational Highlights and Anticipated Upcoming Milestones

Resecabtagene autoleucel (rese-cel) for autoimmune diseases

Cabaletta is advancing rese-cel as an investigational CAR T cell therapy designed to reset the immune system in patients living with autoimmune diseases. Following a single, weight-based intravenous infusion after discontinuation of immunomodulators, rese-cel has shown the ability

to deliver an immune system reset in treated patients across multiple autoimmune diseases, leading to compelling clinical outcomes that have persisted over time. Cabaletta is evaluating rese-cel across the RESET (REstoring SElf-Tolerance) clinical development program, which includes multiple ongoing company-sponsored trials in rheumatology, neurology, and dermatology with disease-specific cohorts designed to evolve directly into registrational studies. Cabaletta is also advancing a program of innovations to broaden and deepen the treatment potential of rese-cel across autoimmune diseases.

Registrational RESET-Myositis data on track for mid-2027 to support first potential BLA submission for rese-cel in 2H27

• Cabaletta continues to anticipate reporting data from the registrational, 17-patient dermatomyositis (DM) and antisynthetase syndrome (ASyS) cohort in mid-2027, including 14 adult DM patients and 3 adult ASyS patients. If successful, Cabaletta plans to submit its first Biologics License Application (BLA) to the U.S. Food and Drug Administration (FDA) in 2H27, inclusive of data from the registrational cohort and the juvenile cohort which may facilitate the potential to be granted a Priority Review Voucher.

• At the European Alliance of Associations for Rheumatology (EULAR) 2026 Congress, Cabaletta presented Phase 1/2 data demonstrating that 80% (8/10) of evaluable adult DM and ASyS patients would have met the primary endpoint of the registrational cohort, with all DM responders maintaining their responses through up to 1.5 years of follow-up. Cabaletta also reported that the first juvenile DM patient achieved an immunomodulator-free moderate Total Improvement Score response at 16 weeks, which was maintained through latest follow-up at 32 weeks.

• Across all 17 RESET-Myositis Phase 1/2 patients reported at EULAR 2026, 100% experienced no or Grade 1 (fever) cytokine release syndrome (CRS) and none experienced immune effector cell-associated neurotoxicity syndrome (ICANS), reinforcing a safety profile supportive of the outpatient dosing option already incorporated in the trial.

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