Mezzion Taps PDE5 Expert to Helm Fontan Drug's Final Push to Market

FORT LEE, N.J. – January 06, 2026 – In a significant move signaling its transition from a development-focused entity to a potential commercial powerhouse, Mezzion Pharmaceuticals has appointed physician-scientist Dr. Ridwan Shabsigh to the newly created role of President and Chief Operating Officer. The appointment comes at a critical juncture for the late-stage biopharmaceutical company as it advances its lead candidate, JURVIGO® (udenafil), through a pivotal global Phase 3 trial for a rare and life-threatening heart condition with no approved treatments.

Dr. Shabsigh, a recognized global authority on the class of drugs to which JURVIGO® belongs, is tasked with steering the company through the final stages of clinical development, regulatory submission, and potential commercial launch. This strategic hire underscores Mezzion's intensified focus on operational execution as it aims to deliver the first-ever FDA-approved therapy for individuals living with Fontan circulation, a complex condition resulting from surgery for single ventricle congenital heart disease (SV-CHD).

A Strategic Appointment at a Pivotal Moment

Mezzion is currently deep into its confirmatory Phase 3 FUEL-2 (Fontan Udenafil Exercise Longitudinal) trial, a global study designed to validate the efficacy and safety of JURVIGO® in adolescents with Fontan physiology. With patient enrollment actively underway in the U.S. and Asia and European sites in start-up, the company is preparing for what it hopes will be a successful New Drug Application (NDA) submission to the U.S. Food and Drug Administration (FDA) and other global regulatory bodies.

Dr. Shabsigh's arrival is timed to fortify this final push. With over 35 years of experience spanning clinical research, drug development, and commercialization, he brings a unique skill set to the new executive position. His extensive background includes guiding multiple therapies to market, with a particular specialization in PDE5 inhibitors—the very class of medication to which JURVIGO® belongs. Prior to joining Mezzion, he served as Chair of the Department of Surgery at SBH Health System in New York City and holds professorships at Weill-Cornell Medical School and the CUNY School of Medicine.

"Ridwan brings a rare combination of physician leadership, late-stage drug development experience and operational execution," said Dean Park, Chairman and Chief Executive Officer of Mezzion, in the company's official announcement. "As we advance the FUEL-2 program and prepare for the next phase of Mezzion's growth, his leadership will be instrumental in strengthening execution and building a scalable organization positioned to deliver long-term value for patients, partners and shareholders."

The Promise of JURVIGO® in a Field of Unmet Need

The stakes for Mezzion's clinical program are exceptionally high, not just for the company but for the approximately 70,000 people worldwide living with Fontan circulation. SV-CHD is a birth defect where a child is born with only one functional heart ventricle instead of two. A series of palliative surgeries culminating in the Fontan procedure reroutes blood flow, allowing the single ventricle to pump blood to the body while deoxygenated blood flows passively to the lungs. While life-saving, this abnormal circulation places immense strain on the body over time.

Patients face a lifetime of progressive, multi-organ complications, including chronic heart failure, Fontan-associated liver disease, kidney dysfunction, and lymphatic disorders. A hallmark of the condition is severely diminished exercise capacity, which impacts every aspect of daily life. Currently, there are no approved pharmacological treatments specifically designed to address the underlying physiology of the failing Fontan circulation. Management relies on off-label use of drugs for adult heart failure and supportive care, with heart transplantation often being the only option for end-stage failure.

JURVIGO®, a highly selective oral PDE5 inhibitor, aims to fill this therapeutic void. By improving blood flow, it has the potential to enhance exercise capacity, improve quality of life, and possibly slow the progression of organ damage. The FDA granted the drug Orphan Drug Designation in 2015, a status reserved for therapies addressing rare diseases.

Dr. Shabsigh acknowledged the gravity of this mission. "Our mission is clear, to successfully complete the FUEL-2 clinical trial and, if approved, make JURVIGO® available to children and adults living with Fontan circulation who face a profound unmet medical need," he stated. "I am honored to join Mezzion and look forward to working alongside patients, families, clinicians and investigators to help deliver a first-in-class therapy and to build Mezzion into a trusted long-term partner to the Fontan community."

Navigating the High-Stakes World of Rare Disease Development

Mezzion's quest for a breakthrough treatment places it firmly in the high-risk, high-reward arena of rare disease drug development. The financial health of its parent company, South Korea-based Mezzion Pharma Co., Ltd. (KOSDAQ: 140410), is intrinsically linked to the success of JURVIGO®. Investor sentiment has been largely positive, with the company's stock showing significant growth over the past year, reflecting confidence in its late-stage pipeline.

This confidence has been bolstered by successful fundraising. The company secured nearly $40 million in 2023 and another $20 million in 2025 to fund the FUEL-2 trial and prepare for commercialization. While the company currently operates at a loss—a common scenario for biotechs heavily investing in R&D—analysts anticipate a turn toward profitability contingent on JURVIGO®'s success. The economic context is compelling; recent analyses estimate the annual economic burden of complex congenital heart disease in the U.S. alone is approximately $74 billion, highlighting the significant value a successful therapy could bring to both patients and the healthcare system.

While Mezzion has a clear lead with JURVIGO® in late-stage trials, the broader research landscape is not static. Other companies and academic institutions are exploring novel approaches, including soluble guanylate cyclase (sGC) stimulators and regenerative medicine, underscoring the urgency to bring an effective treatment to market.

The Road Ahead: From Clinical Trial to Commercialization

The path forward is sharply defined. The FUEL-2 trial, which builds upon data from the preceding FUEL-1 study, is designed to demonstrate a statistically significant improvement in the primary endpoint: peak oxygen consumption (VO2) during exercise. The trial's focus on an adolescent population (ages 12-18) is strategic, targeting a group where intervention may have a meaningful impact on long-term outcomes.

This is where Dr. Shabsigh's specific expertise becomes paramount. His deep knowledge of PDE5 inhibitors and his track record of shepherding drugs through regulatory hurdles and onto the market provide Mezzion with seasoned leadership precisely when it's needed most. His role will extend beyond clinical oversight to building the commercial infrastructure necessary for a successful product launch, a complex undertaking that involves market access, physician education, and patient support programs.

Further strengthening its position, Mezzion recently announced a U.S. patent allowance for udenafil's use in Fontan patients, which could provide market exclusivity into the early 2040s. This intellectual property protection is a critical asset that enhances the long-term value proposition for investors and provides a durable foundation for the company's growth.

As the FUEL-2 trial continues enrolling patients across the globe, the appointment of Dr. Shabsigh signals Mezzion's clear intent to not only cross the regulatory finish line but to be fully prepared for the commercial and community engagement that follows, potentially transforming the therapeutic landscape for a generation of Fontan patients.