RAD-140 (Testolone) Research Guide: Dosing, Safety & Status (2026)

RAD-140, also called Testolone, is a selective androgen receptor modulator (SARM). A SARM is a lab-made compound that switches on the androgen receptor, the same receptor that testosterone uses. The goal of a SARM is to act mostly on muscle and bone while acting less on tissues like the prostate and skin.

RAD-140 is taken by mouth. It was first made by Radius Health and is now studied by Ellipses Pharma as an investigational cancer drug under the name vosilasarm (EP0062). Outside of those trials, RAD-140 is sold online as a "research chemical." It is not a legal dietary supplement and is not approved for human use.

Human research on RAD-140 is early and narrow. It has mostly been studied as a possible cancer treatment, not as a muscle-building product. In some breast cancers, the androgen receptor can act like a brake on tumor growth, so researchers tested whether turning it on could slow the cancer.

In the first-in-human Phase 1 trial (NCT03088527), postmenopausal women with ER+/HER2- metastatic breast cancer took RAD-140 by mouth. The daily doses studied ranged from 50 mg to 100 mg, and the provisional maximum tolerated dose was reported as 100 mg once daily. Researchers reported an acceptable early safety profile and some signs of anti-tumor activity. Even so, a notable share of participants developed raised liver enzymes (AST and ALT) and raised bilirubin while under close medical supervision. This is not a dosing recommendation.

A reformulated version (EP0062 / vosilasarm) is now in an ongoing Phase 1/2 cancer trial (NCT05573126), sometimes combined with other cancer drugs. Other human studies gave healthy volunteers very small "micro-doses" only to map how the body breaks RAD-140 down, which helps anti-doping labs detect it. No trial has tested RAD-140 for bodybuilding, and no SARM has ever finished full approval.

The Swolverine RAD-140 dosage guide presents these numbers as common user-reported ranges, not verified medical guidance. They are included here because readers search for them, but they do not override the liver-injury reports, testosterone-suppression concern, FDA status, WADA ban, or lack of approved human-use labeling.

Administration is usually discussed as oral RAD-140 in liquid or capsule form. For liquid products, the article recommends an accurate oral syringe instead of estimating drops. It also notes that taking RAD-140 with a small meal may improve gastrointestinal comfort for some users, while late-night dosing may be a poor fit for people who find it stimulating.

Because RAD-140 can suppress natural hormone production, the article discusses post-cycle therapy (PCT) as something users commonly consider after a cycle. It describes a typical PCT window as around 4 weeks post-cycle and mentions SERMs such as tamoxifen or clomiphene as common anecdotal approaches. Those are prescription medications and should only be used with appropriate medical supervision.

The Phase 1 cancer-trial doses described earlier are a separate clinical research context and are not a physique-use dose guide. If you are dealing with hormone, recovery, liver, lipid, or body-composition goals, the practical next step is a conversation with a qualified clinician who can review your bloodwork and history.

This RAD-140 dosage chart summarizes the anecdotal user-reported daily ranges and cycle framing discussed above. It is included as a visual reference only, not FDA-approved dosing guidance or a safe-use recommendation.

Most real-world interest in RAD-140 is about body composition: building muscle, getting stronger, and "recomp" (losing fat while keeping muscle). It is often discussed in gym, fitness, and online communities as a "legal-seeming" alternative to anabolic steroids, and it is frequently grouped with other SARMs like ostarine and ligandrol.

It is important to separate popularity from proof. Wide online discussion does not equal evidence that RAD-140 is safe or that it works the way ads claim. The only human trials are early cancer studies, and the published muscle-building "results" come from anecdotes, not controlled research. The same communities have also produced the liver-injury case reports below.

In plain terms, RAD-140 attaches to the androgen receptor and switches it on. When that receptor is active in muscle and bone, it can signal those tissues to grow. That is the effect people are usually thinking of when they search for RAD-140.

The "selective" idea is that RAD-140 is meant to act strongly on muscle and bone and more weakly on the prostate and skin. Its chemistry is built around an oxadiazole ring with a benzonitrile group, which is a different structure from the four-ring "steroid nucleus." That structural difference is why RAD-140 is called nonsteroidal.

The honest limit here is that "selective" does not mean "side-effect free." Human data is thin, and the published harms below show the liver and natural hormone system can still be affected. Most of what is known about how RAD-140 acts in muscle comes from animal and cell studies, not large human trials.

Multiple peer-reviewed case reports describe drug-induced liver injury (DILI) in people who took RAD-140 for muscle growth. The pattern is usually cholestatic, which means bile flow is blocked, leading to jaundice (yellow skin and eyes), dark urine, itching, and very high bilirubin. Reported cases include young, previously healthy men, with onset after only a few weeks of use in some reports.

Doctors note that the liver usually recovers after stopping RAD-140, but recovery can take 3 to 5 months, and liver values sometimes get worse before they get better. In the most severe published cases, clinicians warn that acute liver failure needing a transplant is possible. A US national drug-injury database (LiverTox) lists RAD-140 among SARMs tied to liver harm.

Because RAD-140 is not approved and has documented liver and hormone risks, it carries clear danger for many groups. This is general safety information, not a screening tool.

As of June 2026, RAD-140 is not approved by the FDA for any use. The FDA treats products sold as SARMs as unapproved new drugs and says they cannot be legally marketed as dietary supplements or drugs in the US. In December 2025, the FDA issued warning letters to companies selling RAD-140 and updated its public warning that bodybuilding products containing SARMs can cause serious liver damage, heart attack, and stroke.

In sports, RAD-140 is named on the 2026 WADA Prohibited List under section S1.2, "Other Anabolic Agents," and is banned at all times, both in and out of competition. USADA enforces this for US athletes. (For context, several peptide hormones are also banned by WADA under section S2, so a WADA ban is not unique to SARMs.) RAD-140 is also on the US Department of Defense prohibited list, so it is banned for military service members.

RAD-140 is a SARM, not a steroid and not a peptide. A peptide is a short chain of amino acids; RAD-140 is a small synthetic molecule. A steroid has a four-ring carbon core; RAD-140 does not. These are different chemical families, even though all three can affect muscle.

A key point for the "is it safer than steroids" question: being nonsteroidal does not mean being safe. RAD-140 still suppresses natural testosterone and has its own documented liver-injury risk.

These internal links point to general research and safety reading rather than use instructions.