Climb Bio, Inc.

On June 5, 2026, Climb Bio, Inc. (the "Company") announced translational pharmacometric modeling and initial Phase 1 safety data for CLYM116, its anti-APRIL monoclonal antibody:

• A translational pharmacokinetic/pharmacodynamic model derived from pooled non-human primate ("NHP") data projected healthy human exposure and dose-dependent IgA suppression for CLYM116, suggesting the potential for less-frequent dosing than first generation anti-APRIL approaches.

• Literature analysis shows strong correlation in IgA reduction between NHP and healthy volunteer studies.

• Global Phase 1 strategy, incorporating parallel healthy volunteer datasets ex-China and China (n≈80, doses 25 mg to 640 mg), expected to support a robust population pharmacokinetic foundation to inform dose selection.

• CLYM116 has been generally well tolerated based on preliminary safety data from healthy volunteers receiving single doses up to 320 mg or placebo (n=49), with no unexpected safety findings reported to date.

o No serious adverse events, dose limiting toxicities, or adverse event related discontinuations observed.

o All adverse events observed were mild to moderate (Grade 1-2), transient, and self-resolving.

o Injection site reactions observed in two patients, both Grade 1, and resolved without intervention.