Spanish pharmaceutical company Ferrer has completed patient recruitment for its PROSPER Phase II clinical trial two months ahead of schedule, enrolling 220 participants with progressive supranuclear palsy (PSP) to test the experimental drug FNP-223. The milestone, achieved on October 6th after just 14 months of recruitment, represents a significant step forward in developing the first potential disease-modifying therapy for this fatal neurodegenerative condition.
Trial Design and Global Scope
The PROSPER study is a randomized, double-blind, placebo-controlled Phase II trial designed to evaluate the efficacy, safety, and pharmacokinetics of FNP-223 in slowing PSP progression. The oral formulation drug is a potent and selective inhibitor of the OGA enzyme, in-licensed from Asceneuron. The study spans 44 centers across the European Union, United Kingdom, and United States.
The trial design includes a six-week screening period, followed by 52 weeks of treatment with either FNP-223 or placebo, and a subsequent four-week follow-up period after treatment completion. The study specifically targets participants with early-stage progressive supranuclear palsy–Richardson syndrome (PSP-RS), a critical stage where early intervention may have the greatest impact on slowing disease progression.
Addressing an Urgent Medical Need
Progressive supranuclear palsy is a rare, rapidly progressive and ultimately fatal neurodegenerative disease that primarily affects people over 60 years old. The condition is a primary tauopathy caused by abnormal accumulation of tau protein in brain areas controlling movement and cognition, particularly in subcortical regions and the brainstem. This protein buildup damages nerve cells and disrupts brain function, resulting in symptoms including loss of balance, difficulty speaking or swallowing, abnormal eye movements, and cognitive or mood disturbances.
Although PSP affects between 5.8 and 6.5 people per 100,000, its impact is profound. Loss of independence typically occurs within a few years, and average life expectancy after diagnosis ranges from 6 to 9 years. To date, no disease-modifying therapies have been approved for PSP, highlighting the critical need for effective treatments.
Expert Perspectives on Trial Progress
Prof. Dr. Med. Günter Höglinger from Ludwig-Maximilian University of Munich, principal investigator and coordinator of the PROSPER study, emphasized the collaborative achievement: "I am deeply grateful to the patients, their caregivers, and the dedicated teams at our academic centers for their outstanding commitment, which has enabled us to reach this important milestone so swiftly. Together, we are making significant progress toward answering a critical scientific question: the role of OGA inhibition in PSP."
Kristophe Diaz, Chief Executive Officer of CurePSP, highlighted the significance of successful enrollment: "Achieving full enrollment in a PSP clinical trial is no small feat, and Ferrer's success with the PROSPER study is both a scientific and human milestone. Behind this progress are patients and families who choose to turn hope into action, and their participation accelerates the entire ecosystem toward meaningful therapies for PSP."
Company Commitment to Rare Disease Research
Oscar Pérez, Chief Scientific Officer at Ferrer, noted the early completion as a key step in the company's commitment to accelerating clinical research programs for complex and rare diseases. "In line with our purpose of using business to fight for social justice, we hope to deliver a potential solution that transforms the lives of people affected by this disease and those around them," Pérez stated.
Ferrer has incorporated input from patients, caregivers, and healthcare professionals into the PROSPER study design, aiming to tailor clinical research to participants' real needs and improve their experience while ensuring more impactful clinical research.
Disease Complexity and Genetic Factors
Identifying PSP at the early stage targeted by the PROSPER study presents significant challenges due to the disease's rapid progression and diagnostic complexity. Genetic cases are uncommon, though more than ten associated genes have been identified, with mutations in the MAPT gene being the main risk factor. The potential role of environmental factors, such as exposure to toxins or infectious agents, remains under investigation.
The successful ahead-of-schedule recruitment demonstrates the urgent need for PSP treatments and the commitment of the global research community to advancing therapeutic options for this devastating condition.
