Japan begins clinical trial of tooth-regrowth drug

Scientists in Japan have begun testing an experimental therapy that could enable humans to regrow teeth for the first time. According to Toregem BioPharma (TBP), the drug is primarily intended for people with congenital tooth agenesis, but it may also benefit individuals who have lost teeth due to injury or tooth decay.

The treatment was developed by researchers at the Kitano Hospital Medical Research Institute in Osaka, affiliated with Kyoto University.

Their work identified a protein that suppresses the growth of dormant tooth buds that remain in the jaw. The experimental drug, TRG-035, is a neutralizing antibody that blocks the activity of this protein, activating dormant tooth buds and stimulating the development of a third generation of teeth.

Preclinical studies in mice and ferrets demonstrated successful tooth regeneration following treatment, supporting the transition to human clinical trials.

The Phase I clinical trial began in September 2024 at Kyoto University Hospital and enrolled 30 healthy men aged between 30 and 65, all of whom had lost at least one permanent tooth. The primary objective was to evaluate the treatment's safety, and preliminary results detected no serious adverse effects among the participants.

The next phase of the trial will involve children aged two to seven with congenital tooth agenesis, a rare condition in which patients are missing six or more permanent teeth. Dental implants are generally not suitable for these children because their jawbones are still developing.

Researchers hope the technology could eventually provide a regenerative treatment for tooth loss caused by decay, trauma, or other diseases.

However, they caution that it is still too early to determine the drug's clinical effectiveness. The complete results of the Phase I trial have not yet been published in peer-reviewed scientific journals, and there is currently no definitive evidence that the treatment can induce the growth of fully functional teeth in humans.

Further studies will also be needed to determine whether the newly formed teeth develop normally, achieve proper bite alignment, and establish full connections with nerves and blood vessels.