Zenas BioPharma, Inc. recently announced that the first subject has been dosed in the Phase 1 trial of ZB021, a novel potentially best-in-class oral IL-17AA/AF inhibitor.

“Dosing the first subject in our Phase 1 trial of ZB021 marks an important milestone for Zenas as we rapidly advance our earlier-stage pipeline and broaden our presence in autoimmune and inflammatory diseases,” said Lonnie Moulder, Founder and Chief Executive Officer of Zenas. “The IL-17 pathway is well validated across a broad range of rheumatic and dermatologic indications, yet no oral therapies directed toward this pathway are approved or in late-stage clinical development. The strength of this established mechanism may support an accelerated path toward registration-directed trials, and we expect to report initial clinical data by year-end.”

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.

ZB021 is a novel potentially best-in-class oral small molecule IL-17AA/AF inhibitor being developed by Zenas BioPharma in partnership with InnoCare Pharma. ZB021 is designed to selectively block the signal transduction pathways of both the IL-17AA homodimer and IL-17AF heterodimer, inhibiting downstream pro-inflammatory cytokine and chemokine release. Preclinical studies have demonstrated potent anti-inflammatory activity, a favorable safety profile, and excellent Absorption, Distribution, Metabolism, and Excretion (ADME) properties. The IL-17 pathway has demonstrated broad utility across many rheumatic and dermatologic indications. Currently, no oral IL-17 inhibitors have been approved or are in late-stage development globally. ZB021’s oral, small molecule profile may offer meaningful advantages over currently approved biologic IL-17 therapies in terms of convenience, compliance, and accessibility. Zenas licensed the exclusive rights from InnoCare Pharma to develop, manufacture, and commercialize ZB021 in all fields of use worldwide, excluding greater China and Southeast Asia.

Zenas is a clinical-stage global biopharmaceutical company committed to becoming a leader in the development and commercialization of transformative therapies for patients living with autoimmune diseases. Our core business strategy combines our experienced leadership team with a disciplined product candidate acquisition approach to identify, acquire and develop product candidates globally that we believe can provide meaningful clinical benefits to patients living with autoimmune diseases. Zenas is advancing two late-stage, potential franchise molecules, obexelimab and orelabrutinib. Obexelimab, Zenas’ lead product candidate, is a bifunctional monoclonal antibody designed to bind both CD19 and FcgRIIb, which are broadly present across B cell lineage, to inhibit the activity of cells that are implicated in many autoimmune diseases without depleting them. We believe that obexelimab’s unique inhibitory mechanism of action and self-administered, subcutaneous injection regimen may broadly and effectively address the pathogenic role of B cell lineage in chronic autoimmune disease. Orelabrutinib is a potentially best-in-class, highly selective central nervous system (CNS)-penetrant, oral, small molecule BTK inhibitor. Orelabrutinib’s mechanism of action targets pathogenic B cells not only in the periphery but also within the CNS. Additionally, it directly modulates macrophages and microglial cells in the CNS, with the potential to address compartmentalized inflammation and disease progression in Multiple Sclerosis (MS). Zenas’ earlier stage programs include ZB021, a novel, potentially best-in-class oral small molecule IL-17AA/AF inhibitor, ZB022, a preclinical, potentially best-in-class, oral, brain-penetrant, TYK2 inhibitor, and ZB014, a preclinical, half-life extended anti-CD19 and FcgRIIb monoclonal antibody. For more information about Zenas BioPharma, please visit https://zenasbio.com/ and follow us on LinkedIn.