Researchers in South Korea have announced promising early data regarding a potential new treatment for progressive supranuclear palsy (PSP), a rare and debilitating neurodegenerative disease. The findings, which offer a glimmer of hope for patients and their families in the U.S. and worldwide, stem from a Phase 2A clinical trial evaluating the drug candidate GV1001.

PSP, often misdiagnosed as Parkinson’s disease due to overlapping symptoms, is characterized by a rapid decline in motor skills, balance, speech, and vision. Unlike Parkinson’s, PSP doesn’t typically respond to levodopa, the standard medication for Parkinson’s, leaving patients wiht limited treatment options.The economic burden is also substantial, with families facing meaningful costs for care and support. According to the National Institute of neurological Disorders and Stroke (NINDS), PSP affects an estimated 3 to 6 people per 100,000 in the United States.

The research, spearheaded by Professor Lee Ji-young of Seoul Medical School (Seoul National University Hospital Operation Seoul Boramae Hospital), focused on a subgroup of PSP patients with Richardson Syndrome (PSP-RS), a particularly aggressive form of the disease. The results were initially presented at the Asia and Oceania Parkinson Society (AOPMC) Luncheon Symposium in Tokyo, Japan, on December 22nd, 2024, and further details were discussed at a media roundtable held at the Korea Press center on December 18th, 2024 facilitated by the Korean Medical Bioscience Association.

GV1001 is being developed by the south Korean pharmaceutical company, GemVax & KAEL. The study investigated the effects of a 0.56mg dose of GV1001 on PSP-RS patients.

Key Findings and Insights

Professor Lee emphasized the rigorous approach taken in analyzing the data to maximize the chances of success in future clinical trials. “Neural degenerative diseases have vrey complex pathology and pathological mechanisms, so there are still no clear reasons or distinct treatment.”

Several key findings emerged from the clinical trial data:

• Improved Outcomes in PSP-RS Patients: Post-hoc sensitivity analysis revealed a 116% betterment in the GV1001 0.56mg dosing group in the PSP-RS subgroup.
• Reduced Disease Progression: Professor Lee highlighted that the PSP grade score decreased in the 0.56mg GV1001 group, while the placebo group saw an increase of 5.19 points,demonstrating a statistically significant difference.
• Stabilized Motor Function: Patients receiving GV1001 0.56mg showed no significant disease progression over six months, suggesting a stabilization of motor skills compared to the placebo group. As Professor Lee stated, “This means that the GV1001 0.56mg dosing group means that the exercise disorder has been maintained and stable.”
• High Treatment Response Rate: The treatment response rate, defined as the proportion of patients showing improvement or stabilization after six months, was 63.64% in the GV1001 0.56mg group, compared to only 25.0% in the placebo group.
• Stable Bulbar and Ocular Motor Function: The GV1001 0.56mg group maintained stable performance on bulbar (speech and swallowing) and ocular motor (eye movement) evaluations.
• Safety Profile: The clinical trial reported no serious drug-related side effects. Professor Lee noted, “this clinical trial was the first in PSP patients, so we collected various safety -related data, and safety data are being collected through extended clinical trials.It is encouraging.”

Expert perspectives and U.S. Implications

While these initial findings are encouraging, experts caution that this is just one step in a long process. Further research, including larger Phase 3 clinical trials, is needed to confirm the efficacy and safety of GV1001.

Professor Shin Jung-hwan of Seoul National University (Seoul National University Hospital) provided context on the prevalence of PSP, stating, “The usual PSP prevalence is estimated at 5 to 10 per 100,000 people, which can be estimated at 5,000 Koreans and 30,000 north American people.” The relatively small patient population underscores the challenges in conducting clinical trials and attracting pharmaceutical investment.

for U.S. patients, this research offers considerable promise. If GV1001 proves to be effective, it could provide a much-needed treatment option for a disease with limited therapeutic interventions. The potential impact on quality of life for both patients and their caregivers would be substantial with the possibility of slowing disease progression and maintaining motor function.

The Road Ahead

The progress of new therapies for PSP is a complex and challenging endeavor. “Neural degenerative diseases have very complex pathology and pathological mechanisms, so there are still no clear reasons or distinct treatment,” explains Professor Lee. However, the results of this phase 2A trial offer a renewed sense of optimism.

Gembags & Kael is expected to move forward with larger, multi-center clinical trials to further evaluate GV1001. These trials will be crucial in determining the drug’s long-term efficacy and safety profile. U.S. patients may have the opportunity to participate in these trials, providing access to cutting-edge treatment and contributing to the advancement of PSP research. Patients interested in participating in clinical trials should consult their physicians and explore resources such as the National Institutes of Health’s ClinicalTrials.gov website.

The PSP community in the U.S., supported by organizations like the CurePSP, remains hopeful that this research will lead to a breakthrough in the fight against this devastating disease.