🦷 What if losing a tooth weren't permanent? Not because of an implant or a denture — but because a single injection could coax your jaw into growing a brand-new tooth, the way it did when you were a kid.

That premise — long the stuff of dental-clinic daydreams — now has a date attached to it. Kyoto-based biotech startup Toregem Biopharma announced it will begin Phase 2 clinical trials of its tooth-regeneration antibody TRG035 this summer, the first time the drug will be given to actual patients suffering from missing-tooth disease. To get there, the company has just raised about ¥850 million (roughly $5.3 million) from venture capital firms in May 2026, on top of roughly ¥1.5 billion it had already secured by 2024.

It is a small round by Silicon Valley standards. But Toregem's progress is being read in Japan as a milestone for something much bigger than dentistry: the country's increasingly serious bet that university spinoffs, super-aged demographics, and patient public capital can together deliver a medical export that no other country has produced first.

"Sprout-a-tooth": what the drug actually does

The shorthand the Japanese press uses for TRG035 is hagae-gusuri — literally "sprout-a-tooth medicine." It is less whimsical than it sounds.

Humans are born with the molecular blueprints for a third set of teeth tucked away inside the jawbone, in dormant structures called tooth germs (or tooth buds). In most people, those buds quietly degenerate after the permanent teeth come in. The Kyoto team's central insight, refined over nearly three decades by oral surgeon Katsu Takahashi, was that a single protein called USAG-1 is the gatekeeper that tells those buds to stop developing.

Knock out USAG-1 in mice, and they grow extra teeth. Inject a neutralizing antibody — a precision-guided protein that binds and blocks USAG-1 — and the same thing happens in normal animals. Later experiments in ferrets, which like humans cycle through two sets of teeth, produced a verified third generation of teeth. The work was published in Regenerative Therapy in 2024.

TRG035 is the humanized version of that antibody: an injectable drug designed to reactivate the dormant tooth-bud machinery already inside the patient. It is not stem-cell therapy, not gene editing, and not a bioengineered transplant. Under Japan's regulatory framework, it is technically classed as an antibody pharmaceutical rather than a "regenerative medicine product," even though regeneration is the point.

A patient cohort that explains the choice of disease

The Phase 2 trial, which is set to begin this summer at Kyoto University Hospital, will enroll 24 children aged 2 to 12 who have severe congenital partial anodontia — a rare genetic condition in which six or more permanent teeth never form at all. Roughly 0.1% of people have it, or about 6,000 patients in Japan.

That choice of target is strategic. Severe oligodontia is recognized by Japan's Ministry of Health, Labour and Welfare as an orphan disease, and TRG035 received orphan-drug designation earlier this cycle — a status that, like in the US and EU, unlocks tax credits, expedited review, and longer market exclusivity. The condition is also one where current options are unenviably bad: children spend a decade or more in dentures that have to be remade as their jaws grow, before eventually transitioning to implant surgery in adulthood.

A Phase 1 safety study, run from late 2024 through 2025 on adult men aged 30 to 65 missing at least one molar, has already wrapped its data collection. As of early 2026, no serious adverse events had been reported, and the final report is due around May. In November 2025, Toregem received feedback from a Pre-IND meeting with the US FDA — an early step toward parallel American trials.

The company is targeting commercial launch around 2030. After congenital anodontia, the longer-range pipeline is far more interesting: tooth loss in adults from periodontal disease, trauma, and ageing-related "oral frailty" — a Japanese clinical concept describing the cluster of chewing, swallowing, and oral-muscle decline that often precedes broader frailty in the elderly.

The cap table is a snapshot of Japan's biotech infrastructure

The roughly ¥850 million Toregem just closed comes on top of a ¥1.5 billion package raised in August 2024, when a Series B round combined private equity from corporate VCs with a grant from the Japan Agency for Medical Research and Development (AMED) — the government body that effectively functions as Japan's NIH.

That AMED component is doing more work than it looks. Through a program called the Drug Discovery Venture Ecosystem Enhancement Project, AMED offers matching grants that can effectively double a biotech's private fundraise. Toregem passed the program's interim "stage-gate" review in February 2026, unlocking another tranche of public money. Foreign investors have noticed: when AN Venture Partners closed a $200 million Japan-focused biotech fund last summer, AMED's matching mechanism was cited as a reason the country is suddenly worth playing in.

The rest of Toregem's cap table reads like a who's-who of Japan's biotech VC scene: Astellas Venture Management, JIC Venture Growth Investments, Mitsubishi UFJ Life Science 4, and Kyoto University Innovation Capital — the venture arm of Kyoto University itself, which is launching a $140 million third fund in early 2026 with Taiwan's government in talks to join as the first foreign LP.

Add University of Tokyo Edge Capital Partners (UTEC), which closed a $326 million sixth fund in July 2025, and you have a picture of the funding stack now sitting underneath Japan's roughly 5,000 university spinouts — nearly triple the count a decade ago.

Where this sits in the global tooth-regeneration race

In the broader regenerative-dentistry world, Toregem is not the only contestant. Research groups at King's College London have pursued bioengineered tooth buds grown in the lab from human cells. Chinese teams at Wuhan University and elsewhere have published progress on stem-cell-based pulp and dentin regeneration. The global dental implant market is a comfortably profitable $4.6 billion business growing at around 9% annually, and incumbents are not about to be displaced overnight.

What sets the Toregem approach apart is, paradoxically, how un-radical it is. Rather than building a tooth in a dish and transplanting it — a path with thorny regulatory and surgical complications — TRG035 wakes up tissue that is already there. That makes it look more like a conventional biologic drug from a manufacturing and approval standpoint, which is part of why it has reached human trials first. Manufacturing is being handled by WuXi Biologics, the Chinese contract drug-maker that produces antibodies for clients worldwide.

Why this is happening in Japan

Two structural facts are worth holding side by side. First, more than 90% of Japanese people aged 75 or older are missing at least one tooth, according to Ministry of Health data. Second, Japan's drug-discovery ecosystem has been quietly rebuilding after a decade of being described — fairly — as a global laggard. New-drug launches by Japanese pharma had been declining for years; AMED, the ¥350 billion ($2.2 billion) startup support package the government rolled out, and the university-VC funds above are part of the answer.

Put the two facts together and a particular kind of innovation looks pretty likely to come out of Japan first: medical technology aimed at the diseases of an aged population, financed by a coalition of public matching money and patient university capital, riding on academic research that was funded for decades before it became commercial.

A tooth-regeneration antibody is not going to save the Japanese economy. But the route Toregem is walking — from a 2007 mouse with extra teeth, to a Kyoto lab, to a corporate spin-out, to a phase 2 trial in pediatric patients, to a planned 2030 launch — is the route a lot of Japanese deep-tech is going to have to walk if the country's startup story is going to mean something globally. For once, that walk now has a real timeline.

What about where you live?

In Japan, the conversation about tooth regeneration sits at an unusual junction — between the immediate hope of families with a rare-disease child, and the long-range question of how a country with the world's oldest population is going to keep its citizens chewing food into their nineties. Has anything like TRG035 emerged in your country's research pipeline? Would you take an injection over an implant if it became available? Tell us how the dental-care system, and the funding behind it, looks where you are.

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USD/JPY conversion in this article uses ¥159 per USD, the prevailing rate in mid-May 2026.