🧠 On October 2, 2026, surgeons at Hokkaido University Hospital in Sapporo injected donor stem cells into the brain of a man in his 50s, around the area damaged in a traffic accident. He lives with severe paralysis on one side of his body.

The hospital called it a first for Japan. Patients in Japan had received the same cells before, in a clinical trial. This was the first use of the therapy, called Akuugo, as a commercial product since Japan approved it in July 2024. Getting here took more than two years, and under the terms of that approval, this patient is also the first entry in the data that will decide whether Akuugo stays on the market.

What happened in Sapporo

Akuugo (vandefitemcel, development code SB623) is made by SanBio, a Tokyo-based company founded in California in 2001. It starts as bone-marrow stem cells from healthy donors, modified with a Notch-1 gene fragment. Once implanted, the cells release FGF-2 and other factors that are thought to help damaged neurons regenerate.

Doctors inject 300 microliters (5 million live cells) at five points along each of three tracks, all through a single small hole in the skull.

According to Hokkaido Broadcasting (HBC), the hospital said there were no serious safety problems after surgery and that the man is gradually showing movements he did not have before. He will continue rehabilitation. Speaking to HTB, the hospital's head of neurosurgery, Miki Fujimura, said that until now there had been little to offer these patients beyond rehabilitation, and that this was among the biggest developments of his decades as a neurosurgeon.

Those early signs come from one patient, days after surgery. The trial behind the approval measured its main result at 24 weeks.

The Hokkaido connection

The study that convinced Japanese regulators, a Phase 2 trial called STEMTRA, was published in the journal Neurology in 2021. Its first author was Masahito Kawabori of the Department of Neurosurgery at Hokkaido University Hospital. According to SanBio, the trial ran at five sites in Japan, 21 in the US and one in Ukraine.

As of September 2026, SanBio said eight hospitals were preparing to offer Akuugo: five universities (Hokkaido, Tokyo, Yokohama City, Osaka, Okayama) plus three others. It expected six patients in the fiscal year ending January 2027. Under the approval conditions, the hospital must be equipped for emergencies, and the doctors must be experienced in brain injury and stereotactic surgery (a technique that uses 3D coordinates to guide instruments to an exact spot in the brain).

Approved in 2024, delivered in 2026

Japan approved Akuugo on July 31, 2024, under its conditional, time-limited pathway for regenerative medicine. The approval is valid for seven years and came with four conditions. The first barred shipments until the company proved commercial batches matched the trial product and won an amended approval. A report carried by the Akita Sakigake Shimpo newspaper called that condition unusual.

At approval, SanBio expected to start shipping between February and April 2025. To meet the condition, the company manufactured three batches, according to the same report. SanBio filed for the amendment on June 12, 2025, and soon pushed its expected timeline from May–July 2025 to August 2025–January 2026. A health ministry panel agreed to lift the restriction on October 16, 2025, and the amended approval came on December 8, 2025.

Akuugo was added to Japan's national insurance price list on May 20, 2026, at 72,716,528 yen (about $460,000) for a single treatment, and went on sale on May 21, 2026. We covered that price and how Japanese insurance shields patients from it in an earlier article. Another four and a half months passed before the first patient was treated.

What the evidence actually shows

STEMTRA randomized 63 people with chronic motor deficits after brain injury, and 61 were analyzed: 46 received cells, 15 had sham surgery. On the Fugl-Meyer motor score, a standard measure of arm and leg function, the cell group improved 8.3 points at 24 weeks against 2.3 for sham (p = 0.040), meeting the trial's main goal.

Secondary endpoints improved but were not statistically significant versus sham. Adverse events were reported in 100% of cell recipients and 93.3% of sham patients, a difference that was not significant, with no dose-limiting toxicity or deaths.

The trial enrolled patients at least 12 months after their injury. The health ministry's guideline for Akuugo allows treatment from six months after injury, for patients whose motor impairment has stabilized and who are moderately or severely disabled. The same guideline notes that clinical data on the product are limited and that its efficacy and safety will be evaluated further in post-marketing trials.

The same cells have also failed before. In January 2019, a US Phase 2b trial in 163 chronic stroke patients missed its primary endpoint. Stroke is a different condition, but the product is the same.

As of October 2026, Akuugo is not approved in the US, where its route runs through a Phase 3 trial whose design SanBio has agreed with the FDA. Japan allowed patients access on the strength of one Phase 2 trial and is collecting the rest of the proof afterward.

The patient is part of the proof

Japan's conditional pathway has a mixed record. HeartSheet, a cell sheet for severe heart failure conditionally approved in 2015, was withdrawn after failing to show efficacy in post-marketing trials. The gene therapy Collategene was withdrawn for the same reason. Others, including Stemirac, a spinal cord injury therapy conditionally approved in 2018, were still within their evaluation period when researchers reviewed the system in a 2025 paper.

Akuugo has until July 2031. Under its third condition, every patient treated until the company reapplies must be included in a post-marketing evaluation. The man in Sapporo is the first of them.

A narrow door

Akuugo is approved only for traumatic brain injury, not for stroke or other kinds of brain damage. SanBio's projections, presented to Japan's insurance pricing council, put use at 39 patients a year at peak, in its 10th year on the market, with sales of 2.8 billion yen (about $18 million). Worldwide, an estimated 55.5 million people lived with chronic disability from brain injury in 2016.

Where you live, do promising therapies reach patients early, with the evidence gathered along the way, or does the system wait for a bigger trial first?

References