The ZB021 Phase 1 trial is supported by robust preclinical data demonstrating a desirable pharmacology and toxicology profile. In addition to potent inhibition of IL-17AA/AF signaling, and anti-inflammatory activity demonstrated in animal models, excellent oral bioavailability was observed across multiple preclinical species, including non-human primates. Together, these data support the potential of ZB021 to be a differentiated oral therapy for autoimmune and inflammatory diseases associated with dysregulated IL-17 signaling.

The Phase 1 study is designed to evaluate the safety, tolerability, and pharmacokinetic profile of single ascending doses (SAD) and multiple ascending doses (MAD) of ZB021 in healthy volunteers and is being conducted in partnership with InnoCare Pharma in China. These data are expected by year-end 2026. Upon completion and evaluation of the SAD and MAD study, Zenas plans to initiate a proof-of-concept (POC) trial in North America to evaluate clinical activity and safety in psoriasis patients with results anticipated in 2027.Given the well-established and validated nature of the IL-17 mechanism, Zenas believes there is potential to advance ZB021 directly from POC into registration-directed trials, which could meaningfully accelerate the path to regulatory approval.