Cabaletta Bio (CABA) investor relations material

Key clinical insights and program updates

• Rese-cel, an autologous CAR T-cell therapy, is designed specifically for autoimmune diseases, using a nine-day manufacturing process and weight-based dosing, showing strong efficacy and safety in nearly 100 patients dosed so far.

• Over 80-85% of patients achieve major clinical responses or remission, often off all medications or on low-dose steroids, with durable effects observed up to two years and evidence of immune system RESET.

• The pivotal myositis program is expected to report data in mid-2027, with a BLA filing planned by year-end, and a pivotal scleroderma program will initiate within 12 months.

• Early data in preconditioning-free settings show promising biological and clinical responses, with ongoing dose exploration to optimize efficacy and safety.

• Juvenile dermatomyositis and scleroderma indications could yield a priority review voucher within 1.5–2 years, addressing urgent unmet needs.

Safety profile and differentiation

• No cases of IEC-HS or severe neurotoxicity have been observed in over 90 patients, contrasting with recent safety-related program pauses at Novartis and BMS.

• 94% of patients had no or only grade 1 CRS, and 97% had no ICANS, indicating a favorable safety profile compared to other CD19 CAR T therapies.

• The nine-day manufacturing process is believed to reduce pro-inflammatory cytokine release, differentiating rese-cel from faster-manufactured products linked to higher toxicity.

• Fast-manufactured CAR T-cells expand more aggressively and trigger higher cytokine levels, which is problematic in autoimmune patients with hyperresponsive macrophages.

• The product’s gentle cytokine profile is considered essential for safety in autoimmune indications, unlike oncology where aggressive expansion is beneficial.

Commercial and manufacturing strategy

• Rese-cel’s one-time infusion model offers a paradigm shift from additive, high-cost chronic therapies, appealing to private insurers seeking cost containment.

• Durability of response beyond two years meets private insurer requirements, with potential for rese-cel to become a first-line or step-through therapy.

• Manufacturing strategy includes multiple suppliers (Lonza, ElevateBio) for launch, with Cellares’ automated platform expected to enhance scalability and flexibility post-launch.

• Cellares-manufactured product has shown comparability to traditional processes, and risk mitigation is ensured by maintaining multiple manufacturing partners.

• The shift to preconditioning-free regimens and automated manufacturing could further expand patient access and commercial viability.