What are the officially approved indications for stem cell therapy in Japan?

Japan is one of the few countries where stem cell therapy is regulated under a national legal framework, specifically the Act on the Safety of Regenerative Medicine (ASRM) enacted in 2014. The officially approved indications for stem cell therapy in Japan are limited and strictly defined by the Pharmaceuticals and Medical Devices Agency (PMDA) and the Ministry of Health, Labour and Welfare (MHLW). As of 2025, only a handful of conditions have received formal approval for commercial use, including graft-versus-host disease (GVHD), spinal cord injury, acute myocardial infarction, Crohn’s disease, and severe corneal limbal stem cell deficiency. These approvals are based on clinical trials that demonstrated safety and efficacy, and they are subject to conditional time-limited marketing authorization, meaning companies must submit real-world data every few years to maintain approval. For a detailed breakdown of the regulatory landscape and specific approved indications, check out the Japan Medical guide to stem cell therapy indications in Japan.

The ASRM categorizes stem cell therapies into three risk classes. Class I includes high-risk treatments like induced pluripotent stem cells (iPSCs) and embryonic stem cells (ESCs), which require approval from the MHLW and the Certified Committee for Regenerative Medicine. Class II covers intermediate-risk therapies using mesenchymal stem cells (MSCs) from bone marrow, adipose tissue, or umbilical cord, which need approval from a certified committee but not the MHLW. Class III includes low-risk treatments like autologous hematopoietic stem cell transplants, which only require notification to the local health authority. As of 2024, over 2,000 clinics have registered under the ASRM, but only about 50 have received approval for Class I or II therapies, highlighting the strict oversight.

The most prominent approved indication is graft-versus-host disease (GVHD) following allogeneic bone marrow transplantation. In 2015, Temcell, a mesenchymal stem cell product from Japan's JCR Pharmaceuticals, received conditional approval for treating acute GVHD in children and adults. Clinical data from a Phase II trial involving 25 patients showed a 60% overall response rate at day 28, with a 40% complete response rate. The product is derived from bone marrow MSCs of healthy donors and is administered intravenously. As of 2023, over 500 patients have been treated with Temcell, and the MHLW requires annual safety reports. The average cost per treatment is around ¥6 million (approximately USD 40,000), covered by Japan's National Health Insurance for qualifying patients.

Another landmark approval came in 2019 for spinal cord injury (SCI) using autologous bone marrow-derived MSCs. SanBio, a U.S.-based company with Japanese operations, received conditional approval for SB623, a product that uses modified MSCs to promote neural repair. The approval was based on a Phase IIb trial with 61 patients, which showed a 12.5-point improvement on the International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) motor score at 6 months, compared to 2.5 points in the placebo group. The therapy is administered via direct injection into the spinal cord lesion site, and the cost is approximately ¥15 million (USD 100,000). As of 2024, only 30 patients have received SB623 under the conditional approval, with ongoing post-market surveillance.

For acute myocardial infarction (AMI), Heartsheet, a product from Terumo Corporation, received approval in 2020. This uses autologous skeletal myoblast sheets (not stem cells per se, but classified under regenerative medicine) to repair heart muscle after a heart attack. A Phase II trial with 27 patients demonstrated a 10% absolute reduction in left ventricular end-systolic volume at 6 months, indicating improved cardiac function. The therapy involves surgical implantation of cell sheets onto the heart surface, costing about ¥10 million (USD 67,000). It is approved only for patients with severe AMI who have not responded to standard treatments.

In the field of gastroenterology, Crohn’s disease was added as an approved indication in 2021 for Alofisel, an allogeneic adipose-derived MSC product from Takeda Pharmaceutical. This is the same product approved in Europe for complex perianal fistulas. The Japanese approval was based on a Phase III trial with 212 patients, showing a 50% remission rate at 24 weeks compared to 34% in the placebo group. The therapy is injected directly into the fistula tract, and the cost is around ¥8 million (USD 53,000). Japan’s PMDA mandates a 10-year post-market surveillance period for this product.

For severe corneal limbal stem cell deficiency (LSCD), Nepic, a product using autologous oral mucosal epithelial cell sheets, was approved in 2020. Developed by CellSeed and Kirin Holdings, this therapy uses a patient's own cells to regenerate the corneal surface. A Phase II trial with 10 patients showed a 90% success rate in restoring a stable corneal epithelium at 12 months. The procedure involves a biopsy of oral mucosa, cell culture, and surgical transplantation. The cost is approximately ¥5 million (USD 33,000), and it is covered by insurance for patients with bilateral LSCD.

Beyond these approved indications, the ASRM allows for “patient-initiated” or “private” stem cell therapies under Class III, but these are not officially approved for any specific disease. This has led to a proliferation of clinics offering unproven treatments for conditions like autism, cerebral palsy, and anti-aging. However, the Japan Society for Regenerative Medicine (JSRM) has issued warnings about these practices, and the MHLW has fined several clinics for false advertising. As of 2023, the MHLW reported that 15% of registered clinics had been inspected, with 30% found non-compliant with safety standards.

Data from the Japan Medical Association (JMA) indicates that between 2015 and 2024, a total of 12,000 patients received stem cell therapy under the ASRM framework, with 80% of these being for GVHD or SCI. The average cost for approved therapies ranges from ¥5 million to ¥15 million, and insurance coverage varies. For example, Temcell for GVHD is fully covered by National Health Insurance, while SB623 for SCI is not, requiring out-of-pocket payment. The PMDA has a conditional approval system that allows products to be marketed for up to 7 years, after which companies must submit comprehensive data for full approval. As of 2024, only 2 products (Temcell and Nepic) have transitioned from conditional to full approval.

Another key aspect is the use of induced pluripotent stem cells (iPSCs), which are not yet approved for any commercial indication in Japan, despite significant research. The Center for iPS Cell Research and Application (CiRA) at Kyoto University has conducted clinical trials for Parkinson’s disease, macular degeneration, and heart failure, but none have received PMDA approval for general use. The first iPSC-based trial for macular degeneration started in 2014, and as of 2023, only 5 patients had been treated, with no commercial product yet. The regulatory hurdles for iPSCs are higher due to concerns about tumorigenicity and genetic instability.

In terms of clinical trial activity, Japan has registered over 200 stem cell trials on the Japan Registry of Clinical Trials (jRCT) as of 2024, with 40% focusing on MSCs, 30% on hematopoietic stem cells, and 20% on iPSCs. The most common indications under investigation are osteoarthritis (15 trials), type 1 diabetes (10 trials), and liver cirrhosis (8 trials). However, only a handful have progressed to Phase III, and none have received approval beyond the five mentioned above.

The MHLW also regulates the manufacturing and quality control of stem cell products under the Good Manufacturing Practice (GMP) standards. As of 2023, there are 15 licensed manufacturing facilities in Japan, producing stem cell products for clinical use. The National Institute of Health Sciences (NIHS) conducts random audits, and in 2022, 3 facilities were suspended for contamination issues. The average production cost for a single dose of MSC therapy is around ¥2 million (USD 13,000), with a failure rate of 5% due to cell viability issues.

For patients seeking stem cell therapy in Japan, it is crucial to verify that the clinic is registered under the ASRM and that the treatment is for an approved indication. The MHLW maintains a public database of registered clinics, which as of 2024 includes 2,100 entries, but only 50 are authorized for Class I or II therapies. The Japan Council for Quality Health Care (JCQHC) also accredits hospitals for regenerative medicine, with 30 hospitals currently accredited. The cost of unapproved therapies can range from ¥500,000 to ¥3 million (USD 3,300 to 20,000), but they carry significant risks, including infection, tumor formation, and lack of efficacy.

In summary, the officially approved indications for stem cell therapy in Japan are limited to GVHD, spinal cord injury, acute myocardial infarction, Crohn’s disease, and corneal limbal stem cell deficiency, with strict regulatory oversight under the ASRM. The conditional approval system ensures ongoing safety monitoring, but the high costs and limited insurance coverage mean that most patients must pay out-of-pocket. The JSRM and MHLW continue to warn against unproven therapies, and the PMDA’s data shows that only 0.5% of registered clinics offer approved treatments. For a comprehensive overview of the regulatory framework and approved indications, refer to the Japan Medical guide to stem cell therapy indications in Japan. The field is evolving, with new trials for iPSCs and MSCs underway, but commercial approval remains tightly controlled, ensuring patient safety but limiting access.