# Ostarine

enobosarm · MK-2866 · GTx-024

https://graded.pl/en/substances/ostarine · Checked: Not yet

Preliminary version. The editors have not finished checking this card, and grades may change.

A SARM still being studied. It raised body mass without fat in older people and cancer patients, with no clear gain in fitness in the largest studies. No such medicine exists, and products sold online are often mislabelled.

> This site is for information and education only. It does not promote or encourage the use or purchase of the substances described and is not medical advice. Many are not authorised as medicines and their safety has not been established. We sell nothing and have no ties to sellers. For health decisions, consult a doctor.

## Short answers

### Does ostarine work?

A SARM still being studied. It raised body mass without fat in older people and cancer patients, with no clear gain in fitness in the largest studies. No such medicine exists, and products sold online are often mislabelled. Muscle mass: grade B, effect in studies. Body mass without fat rose in early and in the largest studies, but only in older adults and cancer patients. The maker paid for the studies. Strength: grade C, conflicting results. Physical function improved in an early study, while the two largest studies went in opposite directions. Top strength was not what they tested.

### Is Ostarine legal?

PL: No approval. The Polish sanitary inspectorate lists ostarine, ligandrol and other SARMs as not allowed in food supplements. EU: No approval. The European medicines database (EMA), which covers EU and national approvals, lists no such medicine (9 October 2026). US: No approval. Not approved. FDA treats bodybuilding products containing SARMs as unapproved drugs.

### Is ostarine banned in sport?

Banned in sport, WADA 2026.

### Is Ostarine safe?

Serious warning.

## What studies show

| | | | |
|---|---|---|---|
| Muscle mass | B | Effect in studies | Body mass without fat rose in early and in the largest studies, but only in older adults and cancer patients. The maker paid for the studies. |
| Strength | C | Conflicting results | Physical function improved in an early study, while the two largest studies went in opposite directions. Top strength was not what they tested. |

## Studies we have read

- Phase III Study of the Effect of GTx-024 on Muscle Wasting in Patients (POWER 1) (ClinicalTrials.gov 2014; Random groups, n=321) https://clinicaltrials.gov/study/NCT01355484
- Effect of GTx-024 on Muscle Wasting in Patients With Non-Small Cell Lung Cancer (POWER 2) (ClinicalTrials.gov 2014; Random groups, n=330) https://clinicaltrials.gov/study/NCT01355497
- Effects of enobosarm on muscle wasting and physical function in patients with cancer: a double-blind, randomised controlled phase 2 trial. (Lancet Oncol 2013; Random groups, n=159) https://pubmed.ncbi.nlm.nih.gov/23499390/
- The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II trial. (J Cachexia Sarcopenia Muscle 2011; Random groups, n=120) https://pubmed.ncbi.nlm.nih.gov/22031847/

## Is it legal

- PL: No approval. No approval. The Polish sanitary inspectorate lists ostarine, ligandrol and other SARMs as not allowed in food supplements. https://www.gov.pl/web/gis/zespol-do-spraw-suplementow-diety (Checked: Not yet)
- EU: No approval. The European medicines database (EMA), which covers EU and national approvals, lists no such medicine (9 October 2026). https://www.ema.europa.eu/en/documents/other/article-57-product-data_en.xlsx (Checked: Not yet)
- US: No approval. Not approved. FDA treats bodybuilding products containing SARMs as unapproved drugs. https://www.fda.gov/drugs/fraudulent-products/certain-bodybuilding-products-put-consumers-risk-heart-attack-stroke-serious-liver-damage-and-more (Checked: Not yet)

## Doping

Banned in sport, WADA 2026. https://www.wada-ama.org/en/prohibited-list

## How much research exists

- Scientific papers: 108
- Studies with random groups: 3
- Registered studies in people: 17
- These are search results. A count shows how much exists, not how good the studies are. 1 Nov 2026.

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Open data: CC BY 4.0, https://creativecommons.org/licenses/by/4.0/