KEY POINTS:
- Japanese researchers have begun human trials of a drug that could regrow teeth by blocking the USAG-1 protein, according to AFP and multiple scientific sources
- Phase I clinical trials launched at Kyoto University Hospital in October 2024 with 30 healthy adult males, according to Toregem BioPharma
- The drug received Orphan Drug designation from Japan’s health ministry in September 2025, per official company announcements
- Researchers aim for commercial availability by 2030, though experts caution the path remains long
A Japanese biotech company has begun the world’s first human trials of a drug designed to regrow teeth, potentially offering an alternative to dentures and implants for millions of people who have lost teeth to decay, injury, or genetic conditions.
Toregem BioPharma Co., Ltd., a Kyoto University spin-off, launched Phase I clinical trials at Kyoto University Hospital in October 2024, according to AFP reporting in December 2024. The trial enrolled 30 healthy adult males aged 30 to 64, each missing at least one molar, with the study scheduled to run through August 2025.
The drug, designated TRG-035, works by blocking a protein called USAG-1 that normally suppresses tooth development, according to peer-reviewed research published in Science Advances in February 2021. The study demonstrated that a single administration of anti-USAG-1 antibodies could regenerate whole teeth in mice and ferrets by reactivating dormant tooth buds.
Dr. Katsu Takahashi, head of Oral and Maxillofacial Surgery at Medical Research Institute Kitano Hospital in Osaka and the research lead, has stated the team’s goal is to help those suffering from tooth loss or absence, according to AFP reporting.
Dr. Takahashi has researched tooth regeneration since 1991, according to company materials from Toregem BioPharma. The company name combines “Tooth Regeneration Medicine” and was founded in May 2020 as a Kyoto University spin-off, according to the company’s official website.
Japan’s Ministry of Health, Labour and Welfare granted TRG-035 Orphan Drug designation on September 29, 2025, for the treatment of severe congenital hypodontia—a condition affecting patients missing six or more permanent teeth, according to an official Toregem BioPharma press release.
The underlying science targets what researchers call “third dentition”—vestigial tooth buds that exist in humans but normally remain dormant. According to the Science Advances paper, blocking USAG-1 enhances BMP (bone morphogenetic protein) signaling, allowing these dormant structures to develop into functional teeth.
Animal studies in mice, ferrets, and dogs showed no significant adverse effects, according to the peer-reviewed research. However, human safety data from the ongoing Phase I trial has not yet been published.
Professor Angray Kang of Queen Mary University of London, commenting to AFP, described the research as “exciting and worth pursuing” while cautioning that clinical development “would not be a short sprint, but by analogy a set of back-to-back consecutive ultra-marathons.”
Dr. Chengfei Zhang, clinical professor at the University of Hong Kong, told AFP the method is “innovative and holds potential” but noted that “outcomes observed in animals do not always directly translate to humans.”
Toregem BioPharma has announced plans for subsequent trials involving children aged 2 to 7 with congenital anodontia, according to company statements reported by JStories. These pediatric trials are planned for the 2025-2027 period, following completion of Phase I adult safety assessments.
The company has partnered with WuXi Biologics to manufacture the humanized monoclonal antibody, according to Labiotech reporting.
Dr. Takahashi has stated the goal of commercial availability “in about five years,” according to multiple news reports from 2024. If successful, the treatment could benefit not only those with genetic tooth deficiencies but potentially anyone who has lost teeth, though broader applications would require additional regulatory approvals.
USC Ostrow School of Dentistry noted in an analysis that “even under optimal conditions, widespread availability is unlikely before 2030,” reflecting the lengthy timeline required for Phase II and Phase III trials before potential commercialization.
The research represents what experts describe as a potentially transformative approach to dental medicine, shifting from artificial replacements toward biological regeneration. However, the path from promising animal studies to approved human treatment remains uncertain, and results from ongoing trials will determine whether this approach can fulfill its promise.
Note: This article corrects errors found in viral social media posts that incorrectly attributed this research to “Dentinova Research Hub” (a UK dental news blog unrelated to this research) and prematurely claimed human trials had “successfully completed” with the drug “proven safe.” Phase I trials remain ongoing as of the most recent verified reports.
