Caribou Biosciences (CRBU) investor relations material

Clinical trial design and patient population

• CaMMouflage phase 1 trial evaluated CB-011, an allogeneic anti-BCMA CAR-T cell therapy, in relapsed/refractory multiple myeloma patients with ≥3 prior therapies, including PI, IMID, and anti-CD38 antibody.

• Patients included both BCMA-naïve and BCMA-exposed cohorts, with a median age of 68.5 years and high-risk, heavily pretreated disease characteristics.

• Single-dose CB-011 was administered after lymphodepletion, with 450M cells selected as the recommended dose for expansion (RDE).

Efficacy and response durability

• In BCMA-naïve patients at RDE, 92% achieved overall response rate (ORR), 83% ≥ complete response (CR), and 91% minimal residual disease (MRD) negativity.

• Deep and durable responses were observed, with 50% maintaining ≥CR at 15 months.

• Robust CAR-T cell expansion and rapid decrease in serum free light chains correlated with clinical responses.

• Initial proof-of-concept demonstrated in a BCMA-exposed patient with ongoing CR after prior cilta-cel therapy.

Safety and immune recovery

• Manageable safety profile with no graft-versus-host disease (GvHD), colitis, parkinsonism, or cranial nerve palsies observed.

• Low rates of grade ≥3 infections and rapid recovery of endogenous T and NK cells contributed to favorable safety.

• Three grade 5 adverse events occurred at RDE, with one related to immune effector cell-associated hematotoxicity.