Questions People Ask

No. No Muse cell product has been approved by the FDA, Japan’s PMDA or, as far as we know, any other regulator.^⁠53,73 The most advanced program, a donor cell product called CL2020, was tested in small trials in Japan. Mitsubishi Chemical Group discontinued it in February 2023 for business reasons and stated no safety or efficacy concern.^⁠54,55

Since July 2026, Muse cell products have been offered through private providers in four U.S. states. The company that licenses them states they have not been evaluated or approved by the FDA.^⁠61,63 Results from the CL2020 trials do not show whether any other product is safe or works.^⁠39,62

If you are considering any stem cell treatment, talk with your own physician, and look for registered clinical trials on ClinicalTrials.gov (opens in a new tab). A listing there is not a review by the FDA, and some listed studies only follow people who obtain products at private clinics.

Disclosure. Dr. Albert is CEO of Vesalius Longevity Labs, which has financial ties to MuseCell Innovations, a company in the Muse cell field. This site sells nothing and does not link to any company’s products.

A Muse cell product, CL2020, has been tested in small early trials for heart attack, stroke, spinal cord injury, ALS, a severe blistering skin disease and brain injury in newborns, and other organs have been studied in animals.^⁠38,40 These results are not enough to show that Muse cells help any condition, and no product is approved.^⁠39,53

This site cannot give medical advice. Your own physician is the best person to ask, and ClinicalTrials.gov (opens in a new tab) lists registered studies. A listing there is not a review by the FDA, and some listed studies only follow people who obtain products at private clinics. See the areas under study.

57 people received CL2020 in six published early trials. No trial was stopped for safety, and investigators judged nearly all serious medical events unrelated to the cells. Serious events did occur, including two deaths judged unrelated, and one seizure in the stroke trial could not be ruled out as related.^{⁠32,33,34,35,36,38,39}

No tumors have been attributed to Muse cells in animal studies or in the small human trials so far.^⁠1,38,39 Follow-up lasted 12 weeks to about 18 months, and trials this small cannot detect rare harms, so long-term safety still needs larger, longer studies.^⁠39

Muse cells occur naturally and need no genetic reprogramming, unlike induced pluripotent stem (iPS) cells, which are made in the lab.^⁠1,47 In lab and animal studies they can form cell types of all three germ layers, a wider range than typical mesenchymal stem cells (MSCs), which mainly form bone, cartilage and fat.^⁠1,49

MSCs are further along in the clinic: an MSC product is FDA approved for one condition, while Muse cells have been tested only in small early trials.^⁠39,52,53 Each type has real strengths. See the full comparison.

This site was prepared by Dr. Pradeep Albert, a longevity expert and regenerative medicine specialist, to explain published Muse cell research in plain language. It sells nothing and does not link to any company’s products.

Disclosure. Dr. Albert is CEO of Vesalius Longevity Labs, which has financial ties to MuseCell Innovations, a company in the Muse cell field. This site sells nothing and does not link to any company’s products. About Dr. Albert

Muse cells (multilineage-differentiating stress-enduring cells) are rare stem cells that occur naturally in the body. They have been found in bone marrow, blood, skin, fat and the connective tissue of many organs.^⁠1,4,11,39 Scientists identify them mainly by a surface marker called SSEA-3, usually together with CD105.^⁠1,3 They were first described in 2010 by Prof. Mari Dezawa’s team at Tohoku University in Japan.^⁠1

In the Japanese trials, Muse cells from healthy donors’ bone marrow were grown, purified and frozen as a standardized product, CL2020, then given through an intravenous drip, without tissue matching or anti-rejection drugs.^⁠39 In animal studies the cells then travel to injured tissue; in people, where the cells go has not been tracked.^⁠16,39

In the CL2020 trials so far, donor Muse cells were given without tissue matching or anti-rejection drugs, and no serious rejection reactions were reported.^⁠34,39 How long donor cells survive in the body, and why they seem to avoid rejection, are still open questions. In one mouse study with a normal immune system, human Muse cells were rejected within 7 weeks.^⁠26

In February 2023, Mitsubishi Chemical Group discontinued CL2020, citing the latest clinical developments, timelines for commercialization and its pharmaceutical business strategy. It stated no safety or efficacy concern.^⁠54 Prof. Dezawa publicly questioned how the company presented the trial data.^⁠56 The exclusive rights returned to Prof. Dezawa and Tohoku University, and Tohoku University was to lead further development.^⁠59

That has not been tested in people. The CL2020 trials used donor cells from healthy volunteers’ bone marrow.^⁠39 Whether a patient’s own Muse cells could be collected and used is an open question researchers are exploring.

Muse cells were discovered by Prof. Mari Dezawa’s team at Tohoku University.^⁠1 Dr. Albert is a regenerative medicine physician who follows and explains this research. The studies cited on this site are the work of the research teams named in each source.

Every scientific statement links to a published source: peer-reviewed studies, trial registries, regulators, and dated company or news statements. Evidence labels show whether a finding comes from laboratory, animal or human studies. The content was last checked against its sources on September 25, 2026. See all sources.