CLYM116 - (NAVIGATE-2)

September 3, 2026: Climb Bio (NASDAQ: CLYM) reported positive initial Phase 1 data for CLYM116, an anti-APRIL monoclonal antibody, and outlined development plans in IgA nephropathy. In the ongoing randomized, double-blind, placebo-controlled SAD/MAD healthy-volunteer study (46 subjects), CLYM116 was generally well tolerated, with no serious adverse events, dose-limiting toxicities, or hypogammaglobulinemia.

A single 320 mg subcutaneous dose produced >90% free APRIL suppression and approximately 60-75% reductions in IgA, Gd-IgA1, and IgM, maintained through 12 weeks. The company said the projected half-life was about 29 days, and PK/PD modeling supports every-12-week dosing.

For next steps, the ongoing Phase 2 NAVIGATE-2 trial in IgA nephropathy is an open-label study evaluating an 800 mg loading dose followed by 400 mg every 8 or 12 weeks, intended to support selection of a Q12W regimen for Phase 3. Climb Bio said a 200 mg/mL formulation enables 400 mg in a single subcutaneous injection, with pre-filled syringe development complete for registrational use.

Upcoming catalysts: additional Phase 1 data plus initial reporting from Mabworks’ Phase 1 healthy-volunteer study in China are expected at a medical meeting in Q4 2026; initial NAVIGATE-2 data are anticipated in H1 2027; Phase 3 initiation is anticipated in 2027.