SARMs regulatory reality: not approved, still banned

Key takeaways

• No SARM has FDA approval for any indication. Enobosarm (MK-2866 / ostarine), the most-studied SARM, went through the Phase 3 POWER cancer-cachexia trials but was never approved .
• All SARMs are prohibited at all times under WADA section S1.2 (other anabolic agents), in and out of competition .
• In 2017 the FDA warned that SARMs in bodybuilding products carry serious risks (liver injury, heart attack, stroke) and are unapproved drugs, not dietary supplements .
• No SARM is a federally scheduled controlled substance. The SARMs Control Act (2018 and 2019) would have made SARMs Schedule III, but neither version passed .
• Independent testing of products sold as SARMs found only 52 percent actually contained a SARM and 25 percent contained substances not on the label, a real inadvertent-doping risk for tested athletes .

What SARMs actually are

Selective androgen receptor modulators (SARMs) are non-steroidal compounds designed to bind the androgen receptor with greater tissue selectivity than testosterone or anabolic-androgenic steroids. The pharmaceutical hypothesis was that SARMs could deliver muscle and bone benefits without the prostate, liver, hematocrit, and HPG-axis liabilities of full androgen-receptor agonists. Multiple compounds (MK-2866 / ostarine, LGD-4033 / ligandrol, RAD-140 / testolone, S-4 / andarine, S-23, YK-11) reached human trials. None reached FDA approval .

The compounds are sold globally through research-chemical channels with 'not for human consumption' labels. That label disclaimer is not a regulatory category. It does not authorize sale for human use, does not change FDA jurisdiction, and does not protect either vendor or buyer from enforcement.

MK-2866 (Ostarine, Enobosarm): the deepest trial record

MK-2866 is the most-studied SARM. GTx developed it as enobosarm for cancer cachexia and muscle wasting and ran two Phase 3 trials (POWER 1 and POWER 2) in non-small-cell lung cancer cachexia, randomizing adults to enobosarm 1 mg or 3 mg daily versus placebo alongside first-line chemotherapy. The co-primary endpoints were lean body mass (by DXA) and physical function (measured as stair-climb power), each scored through a responder analysis . Enobosarm improved lean body mass, but the physical-function co-primary was not met, so the co-primaries failed overall and the FDA did not approve enobosarm for cancer cachexia .

Enobosarm did not stop there, and it still has no approval. It was tested in a Phase 2 trial for stress urinary incontinence in postmenopausal women (ASTRID, NCT03241342), which completed but missed its primary endpoint . More recently it has been repositioned to preserve lean muscle mass in people taking GLP-1 weight-loss drugs, with a completed Phase 2 body-composition study . None of those programs has produced an FDA-approved enobosarm product as of 2026-07-08.

Trial-level safety mirrored the SARM class: even at the low trial doses, enobosarm and other SARMs lowered total testosterone, SHBG, and HDL cholesterol, consistent with central androgen-receptor activity, and mild liver enzyme elevations were reported . Body-composition use at the 10 to 25 mg daily doses cited by community sources runs well above the studied trial range.

LGD-4033 (Ligandrol): phase 1 healthy-men data

LGD-4033 reached Phase 1 in healthy men. Basaria and colleagues published a 2013 randomized placebo-controlled study of LGD-4033 at 0.1, 0.3, and 1.0 mg daily for 21 days in 76 healthy men. Lean body mass increased dose-dependently, while total testosterone, SHBG, and HDL cholesterol all dropped dose-dependently. The trial was designed for safety and short-duration pharmacology, not for body-composition outcomes .

Subsequent academic publications described LGD-4033 hepatotoxicity case reports in users taking community doses (5 to 10 mg daily) for several weeks, with elevated transaminases that resolved on discontinuation in most cases . No Phase 2 or Phase 3 efficacy trial in any indication has been published for LGD-4033 since the original Phase 1 program.

RAD-140 (Testolone): first-in-human oncology trial

RAD-140 (testolone) was discovered by Radius Health and reached a Phase 1 first-in-human trial in postmenopausal women with hormone-receptor-positive breast cancer (NCT03088527, later sponsored by Stemline Therapeutics). The 20-patient study tested escalating oral doses for tumor response and safety. The program did not advance to Phase 2 or Phase 3, and no company has sought FDA approval .

Outside that trial, RAD-140 has no published controlled human efficacy data for any indication. Body-composition use at the community-cited 5 to 20 mg daily doses is unsupported by any trial and far exceeds the only completed human study, an oncology safety and tolerability program in a non-overlapping population . Hepatotoxicity and aggression or mood-change case reports have been described in the academic literature .

FDA posture

In 2017 the FDA warned consumers that SARMs sold in bodybuilding products carry serious safety risks, including liver injury, increased risk of heart attack and stroke, and life-threatening reactions, and that these products are unapproved drugs rather than dietary supplements. The agency has issued warning letters to companies selling SARM-containing products and has flagged enforcement against bulk-substance distribution .

The 'research only' or 'not for human consumption' label is not a regulatory category. It does not change FDA jurisdiction, it does not authorize sale for human use, and it does not protect a vendor or buyer if the product is sold or used as an unapproved drug. FDA enforcement has targeted vendors regardless of the disclaimer language.

Not federally scheduled, and the SARMs Control Act never passed

SARMs are unapproved drugs, but they are not federally scheduled controlled substances. There is no DEA schedule for SARMs. Congress has tried: the SARMs Control Act of 2018 (S.2742) and the SARMs Control Act of 2019 (S.2895) would each have added SARMs to Schedule III of the Controlled Substances Act, alongside anabolic steroids. Neither bill was enacted, and no later version has become law .

So possession of a SARM is not a federal controlled-substance offense today. State law can differ in principle, because states schedule substances independently, but there is no reliable public record of a US state having placed LGD-4033, RAD-140, or other SARMs on its own controlled-substance schedule. Treat any vendor claim that SARMs are 'legal' as marketing, not a legal opinion: the unapproved-drug status and the anti-doping ban apply across the US no matter what the packaging says.

WADA prohibition is unconditional

SARMs are listed under section S1.2 (other anabolic agents) of the WADA prohibited list and are banned at all times, in and out of competition . That covers ostarine, ligandrol, andarine, RAD140, S-23, YK-11, and their chemical analogs. Cardarine (GW-501516), a PPAR-delta agonist often sold alongside SARMs, is not a SARM but is prohibited at all times too, listed by WADA under the metabolic-modulators class .

USADA and other national anti-doping organizations regularly publish sanction notices for athletes testing positive for SARM metabolites. A meaningful fraction of SARM-positive cases trace to contaminated dietary supplements rather than intentional use, and USADA has flagged ostarine specifically as a frequent supplement contaminant .

Supplement contamination: the inadvertent-positive risk

Independent testing of products sold as SARMs has repeatedly found mislabeling and contamination. In a JAMA analysis of 44 products marketed as SARMs, only 52 percent actually contained a SARM, 39 percent contained a different unapproved drug, 9 percent contained no active compound at all, and 25 percent contained substances not listed on the label. Only 41 percent of the products contained the amount of active compound the label claimed .

For a tested athlete, that is a real inadvertent-positive risk even without knowingly using a SARM. USADA recommends third-party supplement certification (such as Informed Sport or Informed Choice) to lower the odds, while being clear that no certification scheme guarantees zero contamination .

Hepatotoxicity, lipids, and cardiovascular risk

Documented adverse-event patterns at community body-composition doses cluster across the major SARMs:

• Drug-induced liver injury: cholestatic or mixed hepatocellular hepatitis associated with LGD-4033, RAD-140, and YK-11, usually weeks into use; most cases resolve on discontinuation, but hospitalization-requiring cases have been reported .
• HDL reductions: oral SARMs suppress HDL cholesterol dose-dependently. In the only randomized SARM trial reporting lipids, LGD-4033 lowered HDL by about 21 percent at 0.3 mg and about 39 percent at 1.0 mg daily over 21 days, both below community body-composition doses . The clinical significance of acute HDL reductions is debated, but the suppression signal is consistent and is one component of the FDA cardiovascular concern.
• HPG-axis suppression: total testosterone and SHBG decline at trial doses; recovery time after discontinuation is variable and not guaranteed .
• Cardiomyopathy and major cardiovascular events: isolated case reports in long-term SARM users; causality is not established, but the signal exists in the published case literature.
• Visual disturbances (S-4 / andarine): yellow or blue visual disturbances and impaired dim-light adaptation are dose-dependent and resolve on discontinuation in most user accounts.

The 'cycle' and PCT conversation, in scope

Community use of SARMs typically frames dosing as a 'cycle' (4 to 12 weeks on) followed by 'post-cycle therapy' (PCT) intended to recover endogenous testosterone production. PCT regimens commonly cite SERMs (clomiphene, tamoxifen) and aromatase inhibitors. None of those compounds are FDA-approved for HPG-axis recovery from SARM use. There are no controlled trials of SARM-cycle PCT efficacy. Recovery time after HPG-axis suppression is variable and not guaranteed.

pepSmart does not provide cycle planning or PCT planning for SARMs. The omission is intentional given the absence of clinical evidence and the regulatory posture above.

What the 'research only' label does not do

• It does not change FDA jurisdiction over the substance.
• It does not authorize sale of the substance for human use.
• It does not protect a buyer from a positive doping test.
• It does not protect a vendor from FDA enforcement.
• It does not make the substance an approved drug or a legal dietary supplement.
• It does not change the WADA prohibited-list status.

Editorial summary

The most-studied SARM (enobosarm / MK-2866) went through Phase 3 for cancer cachexia without approval. The next two most-discussed SARMs (LGD-4033, RAD-140) have only short first-in-human or Phase 1 data in healthy or oncology populations. None has FDA approval. All are WADA-prohibited at all times. None is a federally scheduled controlled substance, and the SARMs Control Act never passed. Hepatotoxicity, HPG-axis suppression, and HDL reductions are documented at community body-composition doses. The 'research only' label is regulatory cosplay.

For research and educational purposes only. Not medical advice.

pepSmart has not commissioned independent clinical review of this article.

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Sources: 14 entries, all primary canon (FDA, PubMed, ClinicalTrials.gov, WADA, USADA) plus the congressional bill record, last reviewed 2026-07-08.