8-K: Cabaletta Bio Announces Promising Clinical Data for Rese-cel in Autoimmune Diseases

Cabaletta Bio reports positive clinical data for rese-cel, showing deepening clinical responses across multiple autoimmune indications with a favorable safety profile.

Summary

• Cabaletta Bio announced updated clinical data from the first 10 patients dosed with resecabtagene autoleucel (rese-cel) across the RESET clinical development program.
• The data, with a cut-off date of January 8, 2025, includes results from the RESET-Myositis, RESET-SLE, and RESET-SSc trials.
• In the RESET-Myositis trial, the first adult dermatomyositis patient maintained a major total improvement score (TIS) improvement at 3 months post-infusion, off all immunosuppressants and steroids.
• In the RESET-SLE trial, 3 out of 4 patients in the non-renal systemic lupus erythematosus (SLE) cohort achieved DORIS remission, and the first patient in the lupus nephritis (LN) cohort achieved a complete renal response (CRR).
• In the RESET-SSc trial, the first patient in the severe skin cohort showed clinically meaningful skin improvements and improved lung function at 3 months post-infusion, after discontinuing all disease-specific therapies.
• Rese-cel consistently demonstrated deep depletion of B cells in the periphery within the first month of infusion.
• B cell repopulation typically started around 2 months post-infusion with a transitional nave phenotype.
• 90% of patients experienced either no cytokine release syndrome (CRS) or grade 1 CRS (fever), and 90% experienced no immune effector cell-associated neurotoxicity syndrome.
• As of February 13, 2025, 26 patients have been enrolled across the RESET clinical development program at 50 clinical sites in the U.S. and Europe.
• The company plans to meet with the FDA in the first half of 2025 to align on registrational trial designs.

Sentiment

Score: 8

Explanation: The document presents positive clinical data and future prospects, indicating a favorable outlook for the company and its lead product candidate. The sentiment is high due to the potential for rese-cel to transform the treatment of autoimmune diseases.

Positives

• Rese-cel shows potential for drug-free remission in patients with refractory myositis.
• Clinical responses were observed in SLE and LN patients off all immunosuppressants and steroids.
• The safety profile of rese-cel appears favorable based on the first 10 patients dosed.
• Deep B cell depletion was consistently observed.
• The company is expanding its clinical network and accelerating enrollment.

Risks

• The forward-looking statements are subject to risks and uncertainties that could cause actual results to differ materially.
• Risks include regulatory filings and potential clearance, demonstrating sufficient evidence of safety, efficacy and tolerability, and clinical trial site activation and enrollment rates.

Future Outlook

Cabaletta anticipates enrolling and completing dosing in multiple disease-specific cohorts in 2025, presenting clinical data at medical meetings, and aligning with the FDA on registrational trial designs for rese-cel in the first half of 2025.

Management Comments

• David J. Chang, M.D., Chief Medical Officer of Cabaletta, stated that the expanding clinical experience with rese-cel underscores its potential to provide compelling clinical responses without the need for immunosuppressants or steroids.
• David J. Chang believes rese-cel has the potential to transform the lives of patients with autoimmune disease.
• Cabaletta intends to include the data when they meet with the FDA to align on registrational trial designs in the first half of 2025.
• Cabaletta believes its expanding footprint of clinical sites in the US and Europe has facilitated its ability to accelerate the pace of enrollment and dosing across the RESET program.
• Cabaletta anticipates that it will generate sufficient data to further clarify rese-cel's profile across multiple indications this year to rapidly deliver its therapeutic potential for autoimmune patients.

Industry Context

Cabaletta Bio is positioning itself as a leader in developing targeted cell therapies for autoimmune diseases, an area with significant unmet need. The company's approach of using CAR T therapy to reset the immune system could be a transformative treatment option compared to current therapies that primarily manage symptoms.

Comparison to Industry Standards

• The document references academic studies and industry data showing that approximately 150 autoimmune patients have been dosed with autologous CAR T constructs, with compelling immunosuppressant-free clinical responses observed across many autoimmune diseases, durable for up to 4 years.
• The frequency and severity of CRS/ICANS events were considerably lower than those observed in cancer patients, with <2% Gr 3+ CRS & Gr 3+ ICANS events observed.
• The rese-cel binder has similar in vitro & in vivo activity to the construct used in academic studies.
• The transmembrane domain in rese-cel is CD8 vs. TNFRSF19 (Troy) utilized in the academic construct, but the two transmembrane domains have not been shown to have a significant difference in function or IFNproduction in preclinical studies.
• The CD8 transmembrane domain is employed in tisagenlecleucel.

Stakeholder Impact

• Shareholders: Positive clinical data may increase investor confidence.
• Patients: Rese-cel offers a potential new treatment option for autoimmune diseases.
• Employees: Successful clinical trials could lead to company growth and job security.
• Suppliers and Partners: Increased demand for manufacturing and clinical trial services.

Next Steps

• Enroll and complete dosing in multiple disease-specific RESET cohorts in 2025.
• Present clinical data on rese-cel at medical meetings throughout 2025.
• Present clinical data evaluating rese-cel without preconditioning from the RESET-PV trial in 2025.
• Align with FDA on registrational trial designs for rese-cel in the first half of 2025.

Key Dates

Keywords

rese-cel, Cabaletta Bio, autoimmune diseases, clinical trials, CAR T therapy, RESET program, myositis, SLE, systemic sclerosis, B cell depletion, DORIS remission, complete renal response, TIS improvement