{"url_path":"/sec/caba/8-k/2026-05-14/item-8-01","section_key":"item-8-01","section_title":"Item 8.01 Other Events.","topic":"sec","document":{"doc_type":"8-K","doc_date":"2026-05-14","source_url":"https://www.sec.gov/Archives/edgar/data/1759138/0001759138-26-000024-index.html","accession_number":"0001759138-26-000024","cik":"0001759138","ticker":"CABA","issuer_name":"Cabaletta Bio, Inc.","edgar_url":"https://www.sec.gov/Archives/edgar/data/1759138/0001759138-26-000024-index.html","primary_entity_key":"0001759138","primary_entity_name":"Cabaletta Bio, Inc."},"word_count":1280,"has_tables":true,"body_markdown":"Item 8.01 Other Events.\n\nOn May 14, 2026, the Company posted to the “Investors & Media” section of the Company’s website at www.cabalettabio.com an updated corporate presentation (the “Corporate Presentation”). A copy of the Corporate Presentation is attached hereto as Exhibit 99.2 to this Current Report on Form 8-K and incorporated herein by reference.\n\nOn May 14, 2026, the Company issued the Press Release presenting its preconditioning-free clinical data and automated manufacturing translational data for rese-cel, which are being presented in poster presentations at the American Society of Gene & Cell Therapy (“ASGCT”) 2026 Annual Meeting. Highlights of the rese-cel clinical and translational data being presented at the ASGCT 2026 Annual Meeting include:\n\nLowest Dose Data from RESET-PV Reinforces PC-free Opportunity to Broaden Patient Reach Across Autoimmune Diseases\n\nCabaletta is presenting clinical and translational data from the first four patients with pemphigus vulgaris treated at the lowest dose of rese-cel without preconditioning. As of April 2, 2026, all four patients had been dosed and completed at least 24 weeks of follow-up. The PDAI Total Activity (\"PDAI\") scores ranged from 22 to 83 at baseline. Key findings from the poster include:\n\n•\nTranslational Profile: PC-free rese-cel demonstrated similar CAR T cell expansion kinetics relative to reported translational data from RESET patients with preconditioning. In all four patients, the magnitude and timing of rese-cel expansion was consistent with RESET patients with preconditioning. Three of the four patients experienced complete peripheral B cell depletion. B cell activating factor serum levels, which may correlate with depth of B cell depletion, were increased and reached the lower end of the range achieved in RESET patients with preconditioning. In the three patients with complete peripheral B cell depletion, repopulated B cells reflected an expected transitional naïve phenotype.\n\n•\nSafety Profile: Rese-cel was generally well tolerated with no dose-limiting toxicities (\"DLT\") or immune effector cell-associated neurotoxicity syndrome. One patient experienced transient fever, or grade 1 cytokine release syndrome (\"CRS\").\n\n•\nClinical Profile: All four patients exhibited initial improvement with clinically meaningful reductions in PDAI total activity scores as early as four weeks. Two of the four patients maintained drug-free compelling clinical responses through 6 months of follow-up. The three patients who exhibited full B cell depletion exhibited the most robust clinical improvements. Serum levels of anti-DSG3 and anti-DSG1 antibodies were reduced with initial improvement in PDAI total activity scores.\n\nThe favorable safety observations in all patients and unanticipated, compelling drug-free clinical responses in two of the four patients treated at the lowest PC-free rese-cel dose are supportive of the plan to continue to explore higher doses of PC-free rese-cel in PV and other autoimmune diseases. PC-free rese-cel data at higher doses from RESET-PV are anticipated in 2H26 and initial data at the lowest rese-cel dose from RESET-SLE™ are expected in 1H26 at the European Alliance of Associations for Rheumatology 2026 Congress, being held from June 3-6, 2026, in London, UK.\n\nAutomated Manufacturing Replicates Process Consistency and Early Clinical Experience from the First Two Autoimmune Patients to Support Future Scalable Supply with Minimal Capital Investment\n\nCabaletta is presenting data highlighting the initial manufacturing and translational data from the first two autoimmune patients dosed with rese-cel manufactured using the automated Cellares Cell Shuttle platform, representing the first use of the Cell Shuttle in any clinical program. As of May 6, 2026, both patients had been dosed and completed at least 4 weeks of follow-up. Key findings from the poster include:\n\n•\nManufacturing Profile: The Cell Shuttle process supported end-to-end, closed and automated manufacturing intended to improve reproducibility, scalability and process control while reducing manual complexity. The first two GMP doses of rese-cel manufactured on the Cell Shuttle met all release specifications with on-time delivery. Critical product quality metrics, including purity, CAR expression, viability, vector copy number, and cytotoxic activity, were within the established quality range based on historical clinical manufacturing runs.\n\n•\nInitial Translational Profile: Rese-cel with automated manufacturing demonstrated similar peak expansion and B cell depletion kinetics, both at similar magnitudes and timeframes, relative to its broader reported translational profile across RESET trials.\n\n \n\nCabaletta believes these initial findings support the continued advancement of the Cell Shuttle automated manufacturing platform as a commercial supplier for rese-cel, if approved, to improve reproducibility and scale over time while maintaining product attributes within established clinical ranges.\n\nForward-Looking Statements\n\nThis 8-K contains “forward-looking statements” of Cabaletta within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including without limitation, express or implied statements regarding: Cabaletta’s business plans and objectives as a whole; Cabaletta's ability to realize its vision of launching curative targeted cell therapies designed specifically for patients with autoimmune diseases; the clinical significance of the data presented, including clinical and translational data from the RESET-PV preconditioning-free cohort and initial automated manufacturing data from patients treated with the Cellares Cell Shuttle; Cabaletta's expectations regarding the potential of preconditioning-free rese-cel to expand patient access and plans to explore higher doses across autoimmune diseases, including the anticipated timing of data therefrom; Cabaletta's ability to successfully complete research and further development and commercialization of its drug candidates in current or future indications, including the timing and results of its clinical trials; Cabaletta's plans to implement automated manufacturing of rese-cel with Cellares’ Cell Shuttle platform and expectations regarding the potential of such platform to improve reproducibility, scalability and process control, including the potential to supply rese-cel at flexible scale with minimal capital investment and among the lowest cost of goods in the industry for autologous cell therapy production; and Cabaletta's expectations around the potential success and therapeutic benefits of rese-cel, including the potential demand from thousands of patients living with autoimmune diseases.\n\n \n\nAny forward-looking statements in this 8-K are based on management’s current expectations and beliefs of future events and are subject to a number of risks and uncertainties that could cause actual results to differ materially and adversely from those set forth in or implied by such forward-looking statements. These risks and uncertainties include, but are not limited to: risks related to regulatory filings and potential clearance; the risk that signs of biologic activity, persistence or clinical response may not inform long-term results or translate across programs; Cabaletta’s ability to demonstrate sufficient evidence of safety, efficacy and tolerability in its preclinical studies and clinical trials of rese-cel; risks that modifications to trial design or approach may not have the intended benefits; risks related to clinical trial site activation, enrollment delays and assessment of clinical trial results; risks related to volatile market and economic conditions and public health crises; Cabaletta’s ability to retain and recognize the intended incentives conferred by Orphan Drug Designation, Fast Track Designation, Regenerative Medicine Advanced Therapy Designation or other designations for its product candidates, as applicable; risks related to Cabaletta’s ability to protect and maintain its intellectual property position; risks related to fostering and maintaining successful relationships with Cabaletta’s collaboration and manufacturing partners; uncertainties related to the initiation and conduct of studies and other development requirements for its product candidates; and the risk that any one or more of Cabaletta’s product candidates will not be successfully developed and/or commercialized. For a discussion of these and other risks and uncertainties, and other important factors, any of which could cause Cabaletta’s actual results to differ from those contained in the forward-looking statements, see the section entitled “Risk Factors” in Cabaletta’s most recent annual report on Form 10-K as well as discussions of potential risks, uncertainties, and other important factors in Cabaletta’s other subsequent filings with the Securities and Exchange Commission. All information in this 8-K is as of the date of this Current Report on Form 8-K, and the Company undertakes no duty to update this information unless required by law."}