Chinook Therapeutics Announces First Patient Enrolled in Pivotal Phase 3 BEYOND Study of Zigakibart (BION-1301) for Patients with IgA Nephropathy

SEATTLE, July 28, 2023 (GLOBE NEWSWIRE) — Chinook Therapeutics, Inc. (Nasdaq: KDNY), a biopharmaceutical company focused on the discovery, development and commercialization of precision medicines for kidney diseases, today announced that the first patient with IgA nephropathy (IgAN) has been enrolled in the BEYOND study, a pivotal phase 3 clinical trial evaluating the safety and efficacy of zigakibart (BION-1301), a potentially disease-modifying anti-APRIL monoclonal antibody.

“Initiation of the phase 3 BEYOND study is an important step towards our goal of providing an innovative treatment option for patients with IgAN, a disease with high unmet need and limited treatment options,” said Eric Dobmeier, president and chief executive officer of Chinook Therapeutics. “The data from our ongoing phase 1/2 trial of zigakibart supports our belief that binding and neutralizing APRIL in patients with IgAN plays a key role in depleting pathogenic galactose deficient-IgA1, reducing proteinuria and preserving kidney function for IgAN patients.”

“I am pleased to see Chinook enroll the first patient in the phase 3 BEYOND study of zigakibart in IgAN and look forward to the study’s continued enrollment,” said Vlado Perkovic, MBBS, PhD, FASN, FRACP, dean of medicine and health and Scientia professor at University of New South Wales and co-chair of the BEYOND study steering committee. “IgAN is the most common primary glomerular disease worldwide with limited treatment options currently available, causing many patients to progress to end-stage kidney disease, requiring dialysis or kidney transplant. With the potential to be disease-modifying based on the encouraging results observed in the phase 1/2 study, I believe zigakibart could be an important new therapeutic treatment option for patients with IgAN.”

About the BEYOND Study
The BEYOND study (see www.clinicaltrials.gov, identifier NCT05852938) is a global, randomized, multicenter, double-blind, placebo-controlled phase 3 clinical trial comparing the safety and efficacy of zigakibart versus placebo in patients with IgAN at risk of progressive loss of kidney function. Approximately 272 patients with biopsy-proven IgAN and eGFR ≥ 30 mL/min/1.73m² will be randomized to receive 600 mg of zigakibart or a matched placebo subcutaneously every two weeks for 104 weeks. An additional exploratory cohort, not included in the primary analysis, will be comprised of approximately 20 subjects (10 subjects per arm) with biopsy-confirmed IgAN and eGFR of ≥ 20 to < 30 mL/min/1.73 m².

The primary efficacy endpoint of the BEYOND study is to evaluate the effect of zigakibart versus placebo on proteinuria as measured by change in urine protein to creatinine ratio (UPCR) from baseline to 40 weeks. Secondary and exploratory objectives include evaluating change in eGFR from baseline to week 104; composite clinical outcome of 30% or 40% reduction in eGFR, eGFR < 15 mL/min/1.73m² or dialysis, kidney transplantation or all-cause mortality; safety and tolerability; impact of zigakibart on disease biomarkers and health-related quality of life, as well as analysis of zigakibart pharmacokinetics and immunogenicity.

About Chinook Therapeutics, Inc.
Chinook Therapeutics, Inc. is a clinical-stage biopharmaceutical company developing precision medicines for kidney diseases. Chinook’s product candidates are being investigated in rare, severe chronic kidney disorders with opportunities for well-defined clinical pathways. Chinook’s lead program is atrasentan, a phase 3 endothelin receptor antagonist for the treatment of IgA nephropathy and proteinuric glomerular diseases. Zigakibart (BION-1301), an anti-APRIL monoclonal antibody, is being evaluated in a phase 3 trial for IgA nephropathy. CHK-336, an oral small molecule LDHA inhibitor for the treatment of hyperoxalurias, is in phase 1 development. In addition, Chinook’s research and discovery efforts are focused on building a pipeline of precision medicines for rare, severe chronic kidney diseases with defined genetic and molecular drivers. Chinook is leveraging insights from kidney single cell RNA sequencing and large CKD patient cohorts that have been comprehensively panomically phenotyped, with retained biosamples and prospective clinical follow-up, to discover and develop therapeutic candidates with mechanisms of action targeted against key kidney disease pathways. To learn more, visit www.chinooktx.com.

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