Mezzion Reports Positive In Vivo Results for Udenafil in ADPKD

Seoul, Korea, Aug. 2, 2026 /PRNewswire/ -- Mezzion Pharma Co., Ltd. today announced positive results from a new in vivo study of udenafil, a novel phosphodiesterase type 5 (PDE5) inhibitor, in autosomal dominant polycystic kidney disease (ADPKD). In a preclinical ADPKD model, udenafil reduced kidney cyst burden and blood urea nitrogen (BUN), a blood marker linked to kidney function, compared with controls. Both findings were statistically significant and consistent across the treatment groups evaluated.

The study also showed evidence of activity on udenafil's intended cyclic guanosine monophosphate (cGMP) signaling pathway in the kidney.

In addition, udenafil produced a statistically significant reduction in a preclinical measure of cardiac hypertrophy, or heart enlargement. Because cardiovascular complications are an important part of ADPKD, this finding supports further study of udenafil's potential effects on cardiac remodeling.

The study was conducted at Mayo Clinic in Florida, with Fouad T. Chebib, M.D., serving as principal investigator. The results build on two earlier preclinical studies in which udenafil inhibited cyst growth and reduced cyst burden. Across these complementary ADPKD models, udenafil has shown activity on its intended cGMP pathway, reduced measures of cystic disease, and improved a biochemical measure used in kidney assessment. Together, the data support clinical evaluation in people with ADPKD.

"These findings strengthen the scientific rationale for advancing udenafil in ADPKD," said Dong Hyun Park, Chairman and CEO of Mezzion. "As previously announced, the U.S. Food and Drug Administration (FDA) indicated that Mezzion's nonclinical data package, together with its prior clinical and safety experience with udenafil, provides a reasonable foundation for clinical development. Udenafil has been studied in multiple clinical programs over approximately 20 years, including studies with multi-year exposure. This experience will help inform ADPKD study design and safety monitoring."

"The consistency across multiple preclinical models is encouraging and supports evaluating udenafil in a well-designed Phase 2b study using established measures of ADPKD progression," said Ronald D. Perrone, M.D., of Tufts Medicine.

"Patients with ADPKD need more treatment options for this serious, lifelong disease," said Ridwan Shabsigh, M.D., FACS, President and COO of Mezzion. "Advancing udenafil in ADPKD gives Mezzion a second rare-disease development program alongside our ongoing Phase 3 FUEL-2 study."

"The preclinical data provide a compelling scientific rationale for clinical evaluation in ADPKD. Unlike vasopressin V2 receptor antagonists, udenafil is being investigated through modulation of the nitric oxide-cGMP pathway, providing a mechanistically distinct therapeutic approach. We look forward to participating in the study," said Professor Yong Chul Kim of Seoul National University Hospital.

ADPKD is a progressive genetic kidney disease affecting approximately 1 in 400 to 1,000 people worldwide. As kidney cysts grow, kidney function can decline and ultimately lead to dialysis or kidney transplantation. ADPKD is also associated with cardiovascular and other complications.

Mezzion plans to advance udenafil into a Phase 2b study in adults at risk of rapidly progressing ADPKD, subject to finalization of the protocol and receipt of regulatory and ethics approvals. The planned study is expected to evaluate kidney volume and function, disease-related biomarkers, pharmacokinetics, safety, and tolerability.

About Mezzion Pharma Co., Ltd.

Mezzion Pharma Co., Ltd., based in Korea and listed on the KOSDAQ (140410), is a clinical-stage biopharmaceutical company focused on developing therapies for rare and underserved diseases. The Company is developing udenafil across multiple potential indications, including Fontan circulation and ADPKD. Udenafil is an investigational product and has not been approved by any regulatory authority.

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SOURCE Mezzion Pharma Co., Ltd.