RAD-140, sold online as “Testolone,” is an experimental oral drug from the class called selective androgen receptor modulators (SARMs). SARMs are non-steroidal molecules designed to activate the androgen receptor in muscle and bone while having less effect on tissues such as the prostate. Radius Health developed RAD-140 and described it in 2011. Its official nonproprietary name is vosilasarm (PubChem).
The most important fact: RAD-140 has never been tested in a controlled trial for muscle, strength or body composition in people. The only published human trial was a small phase 1 cancer study in 22 postmenopausal women with metastatic breast cancer. It is not approved by the FDA for any use, and FDA treats products sold as SARMs as unapproved drugs. Its “muscle-building” reputation rests on rat and monkey studies, while the human literature on recreational use consists mostly of case reports of liver injury.
This page summarizes what the preclinical studies, the phase 1 trial, case reports and regulators report. It is for education only and is not medical advice.
| Property | Detail |
|---|---|
| Drug class | Non-steroidal selective androgen receptor modulator (SARM) |
| Other names | Testolone; vosilasarm (INN/USAN); EP0062 |
| Developer | Radius Health (2011); now studied in breast cancer as EP0062 by Ellipses Pharma |
| Route | Oral |
| Doses studied in people | 50, 100 and 150 mg once daily in a phase 1 breast cancer trial; 100 mg/day was the maximum tolerated dose |
| Half-life | 44.7 h in the phase 1 trial (postmenopausal women with breast cancer) |
| Key mechanism fact | Binds the androgen receptor (Ki 7 nM vs 29 nM for testosterone in vitro); not a steroid |
| FDA status | Not approved for any use; FDA calls products marketed as SARMs unapproved new drugs |
| US controlled-substance status | Not listed on the DEA controlled substances list (August 2026 edition) |
| WADA status | Prohibited at all times (S1.2, named in the 2026 list) |
What it is
RAD-140 is a small synthetic molecule, formula C₂₀H₁₆ClN₅O₂, molecular weight 393.8 g/mol (PubChem). It contains a 1,3,4-oxadiazole ring and two benzonitrile groups. It has no steroid skeleton, so it is not an anabolic steroid in the chemical sense, even though it acts on the same receptor.
Radius Health scientists reported its design and preclinical testing in 2011 (Miller et al., ACS Med Chem Lett 2011). An earlier lead compound was rapidly broken down by liver enzymes, so the chemists blocked the vulnerable position on the molecule. RAD-140 was the result. In laboratory tests it:
- bound the androgen receptor with a Ki (binding constant; lower means tighter) of 7 nM, compared with 29 nM for testosterone and 10 nM for DHT;
- showed little binding to other steroid receptors, with the progesterone receptor the closest off-target (IC50 750 nM, vs 0.2 nM for progesterone itself);
- was stable in rat, monkey and human liver microsomes (half-life over 2 h in that assay).
Later, Radius studied it as a breast cancer drug. In breast cancer cells it acted as an androgen receptor agonist and suppressed estrogen receptor signaling, including the ESR1 gene. In patient-derived xenograft models (human tumors grown in animals) it slowed the growth of AR-positive/ER-positive breast cancers (Yu et al., Clin Cancer Res 2017).
About “tissue selectivity” and anabolic:androgenic ratios. Marketing often describes RAD-140 as building muscle with little androgenic effect, sometimes with a precise ratio. The selectivity data come from rats, where RAD-140 increased the weight of the levator ani muscle at much lower doses than it took to stimulate the prostate. We found no human study that measured tissue selectivity. In the one human trial, RAD-140 lowered SHBG in 18 of 18 women and raised PSA (a prostate-type androgen marker) in 16 of 20, which shows clear androgen activity in people.
Pharmacokinetics
Human pharmacokinetic data come from the phase 1 trial and from a doping-control study:
| Measure | Finding | Source |
|---|---|---|
| Elimination half-life | 44.7 h, which supported once-daily dosing | Phase 1, 50–150 mg/day in women with breast cancer (LoRusso et al., 2022) |
| Time to peak in urine | 2–6 h after a micro-dose | 5 adult male volunteers per arm, 1–50 µg doses (Wagener et al., Metabolites 2022) |
| Accumulation | Urine levels 2.4-fold higher after the fifth daily 50 µg dose than after the first | Same study |
| Urine detection window | Up to 29 days after a single 50 µg dose | Same study |
| Metabolism | Hydroxylation, glucuronidation, sulfation and hydrolysis; several metabolites first identified in human urine | Same study |
In animals, oral bioavailability (the share of a dose that reaches the blood) was 27–63% in rats and 65–75% in monkeys (Miller et al., 2011).
The micro-dose study used amounts thousands of times smaller than the 50–150 mg doses in the cancer trial. Its long detection window explains why athletes who unknowingly take contaminated supplements can test positive weeks later.
Regulatory status
- FDA. No SARM is approved. FDA’s consumer page states that products sold as SARMs “have not been approved by the FDA” and lists risks including heart attack or stroke, liver injury and acute liver failure, infertility and testicular shrinkage (FDA, 2025).
- Warning letters. In December 2025 FDA sent warning letters to online sellers, including one naming “RAD-140” (sold as Testolone). The letter states that products marketed as SARMs are unapproved new drugs, and that “research use only” labeling does not change this (FDA warning letter, 2025).
- DEA. RAD-140 is not on the DEA’s alphabetical list of controlled substances (DEA, August 2026). This means it is not a scheduled drug like testosterone; it does not make sales legal.
- WADA. The 2026 Prohibited List names RAD140 under S1.2 “Other anabolic agents,” prohibited at all times, in and out of competition (WADA 2026 List).
What the research shows
Muscle and bone: animal data only
All muscle and bone data for RAD-140 come from animals. They should not be read as evidence of effects in people.
| Study | Model | Main findings |
|---|---|---|
| Miller et al., 2011 | Young castrated and intact rats, 11 days | Levator ani muscle weight rose from 0.03 mg/kg (castrated) and 0.1 mg/kg (intact); prostate stimulation above intact control only at 30 mg/kg |
| Miller et al., 2011 | Young male cynomolgus monkeys, 28 days, 3 per dose | Body weight rose more than 10% at 0.1 mg/kg; lean-mass changes on DEXA were not statistically significant; LDL, HDL and triglycerides fell |
| Brown et al., 2023 | Young and adult female mice, 5 mg/kg for 10 weeks | No strength gain; higher frailty scores and mortality risk than controls (p ≤ 0.042) |
| Heinze et al., 2025 | Old male and female mice, 5 mg/kg/day for 6 weeks | No change in frailty; males kept more lean mass and bone density; no benefit in females; grip strength unchanged in both sexes |
The results are mixed even in animals. The early rat and monkey data from the developer were positive. Independent mouse studies found no strength benefit and, in young and adult female mice, signs of harm.
Breast cancer: the only human trial
The first-in-human phase 1 trial enrolled 22 heavily pretreated postmenopausal women with ER-positive/HER2-negative metastatic breast cancer (LoRusso et al., Clin Breast Cancer 2022). It used a “3 + 3” dose-escalation design, with no control group.
| Dose (once daily) | Patients |
|---|---|
| 50 mg | 6 |
| 100 mg (maximum tolerated dose) | 13 |
| 150 mg | 3 |
| Outcome | Result |
|---|---|
| Partial tumor response | 1 patient (at 100 mg/day) |
| Clinical benefit rate at 24 weeks | 18.2% |
| Median progression-free survival | 2.3 months |
| SHBG decreased | 18 of 18 patients |
| PSA increased | 16 of 20 patients |
The trial is listed as completed on ClinicalTrials.gov (NCT03088527). A phase 1/2 study of the same molecule, under the code EP0062, alone and in combination therapy for AR-positive/ER-positive/HER2-negative advanced breast cancer, began in 2023 and is listed as recruiting (NCT05573126).
Side effects and risks
Liver injury
Liver problems are the best-documented risk, in both the trial and in recreational users.
In the phase 1 trial (LoRusso et al., 2022):
| Adverse event | Share of patients |
|---|---|
| Raised AST (a liver enzyme) | 59.1% |
| Raised ALT (a liver enzyme) | 45.5% |
| Raised total bilirubin | 27.3% |
| Grade 3/4 AST/ALT elevation | 22.7% |
| Grade 3/4 hypophosphatemia (low blood phosphate) | 22.7% |
| Vomiting, dehydration, decreased appetite, weight loss | 27.3% each |
| Any treatment-related adverse event | 77.3% (31.8% grade 3; none grade 4) |
These were women with advanced cancer, many with prior treatments, so not every event can be pinned on RAD-140. Still, liver enzyme rises were the most common adverse events.
Case reports describe a consistent pattern in young and middle-aged men who bought RAD-140 online: jaundice, itching and cholestatic liver injury (impaired bile flow), usually improving after the product was stopped:
- A 52-year-old man had biopsy-confirmed drug-induced liver injury after products containing RAD-140, one also with LGD-4033; enzymes normalized about 3 months after stopping (Barbara et al., ACG Case Rep J 2020).
- A 24-year-old man developed jaundice after 5 weeks of RAD-140, with a peak bilirubin of 38.5 mg/dL; it resolved after stopping (Leung et al., Ochsner J 2022).
- A 43-year-old man needed hospital admission with a bilirubin of 708 µmol/L, with a mixed cholestatic and hepatitic pattern (Perananthan and George, Aust Prescr 2024).
- A young man who took a product with RAD-140 and andarine (S4) developed severe cholestatic injury that worsened despite stopping it and corticosteroids, needing plasmapheresis and intensive care (Dao et al., Proc Bayl Univ Med Cent 2026).
A systematic review of SARM safety in generally healthy adults counted 15 case reports of drug-induced liver injury across all SARMs, and a mean 7.1% rate of raised ALT in SARM clinical trials (Vignali et al., J Xenobiot 2023). Case reports cannot prove cause or show how common injury is. Many users took unverified products or more than one compound.
In the 2011 monkey study, no animal had liver enzymes more than twice its baseline over 28 days (Miller et al., 2011). The human data above show that this did not carry over to people.
Heart
Isolated case reports have linked RAD-140 to heart inflammation:
- A 32-year-old man with type 1 diabetes developed presumed acute myocarditis (inflammation of the heart muscle) with a troponin I of 77.1 ng/mL after using RAD-140 bought online (Padappayil et al., Cureus 2022).
- A 16-year-old boy developed myopericarditis after his first dose of a product sold as RAD-140 (Schwartzman et al., JACC Case Rep 2024).
These single cases do not establish cause. FDA lists an increased risk of heart attack and stroke among the potential harms of SARMs as a group (FDA, 2025).
Hormones, lipids and fertility
No published study has measured what RAD-140 does to testosterone, LH, FSH or sperm counts in men. The claim that it “doesn’t suppress” natural testosterone is therefore untested, not proven. What is known:
- in the phase 1 trial, SHBG fell in every woman measured and PSA rose in most (LoRusso et al., 2022);
- in monkeys, LDL, HDL (“good”) cholesterol and triglycerides fell (Miller et al., 2011);
- FDA lists infertility and testicular shrinkage among potential SARM harms.
Who should not use it
RAD-140 is an unapproved investigational drug with no established safe dose for any use. Its only human testing has been in cancer patients under trial monitoring. Athletes subject to anti-doping rules also risk a violation, including from contaminated supplements, because RAD-140 can be detected in urine for weeks.
Quality and contamination
Products sold online as “RAD-140” are not made under drug manufacturing standards. A JAMA analysis bought 44 products marketed as SARMs from internet sellers (Van Wagoner et al., JAMA 2017):
| Finding | Products |
|---|---|
| Contained at least one SARM | 23 of 44 (52%) |
| Contained another unapproved drug (e.g. ibutamoren, GW501516, SR9009) | 17 (39%) |
| No active compound detected | 4 (9%) |
| Contained substances not on the label | 11 (25%) |
| Amount matched the label | 18 (41%) |
Several of the liver injury cases above involved products that contained more than one compound. Related pages: Ostarine, Ligandrol, Andarine, RAD-150.
Key takeaways
- No human muscle data. RAD-140 has never been tested for muscle, strength or body composition in a controlled human trial; those claims rest on rat and monkey studies.
- One small human trial, in cancer. A phase 1 trial in 22 women with metastatic breast cancer found a half-life of about 45 hours and a maximum tolerated dose of 100 mg/day.
- Liver injury is the main documented risk. Liver enzyme rises were the most common adverse event in the trial, and multiple case reports describe cholestatic jaundice in recreational users, some severe.
- “Selective” is not “non-androgenic.” In people, RAD-140 lowered SHBG and raised PSA; effects on male testosterone and fertility have not been studied.
- Unapproved and banned in sport. FDA treats products sold as SARMs as unapproved drugs, and WADA prohibits RAD140 at all times; urine detection can last weeks.
- Product contents are unreliable. Internet SARM products often contain other drugs, the wrong amount, or nothing at all.
Sources
- Miller CP, Shomali M, Lyttle CR, et al. Design, synthesis, and preclinical characterization of the selective androgen receptor modulator (SARM) RAD140. ACS Med Chem Lett. 2011;2(2):124–129. PubMed.
- Yu Z, He S, Wang D, et al. Selective androgen receptor modulator RAD140 inhibits the growth of androgen/estrogen receptor-positive breast cancer models with a distinct mechanism of action. Clin Cancer Res. 2017;23(24):7608–7620. PubMed.
- LoRusso P, Hamilton E, Ma C, et al. A first-in-human phase 1 study of a novel selective androgen receptor modulator (SARM), RAD140, in ER+/HER2- metastatic breast cancer. Clin Breast Cancer. 2022;22(1):67–77. PubMed.
- National Library of Medicine. Phase 1, first-in-human study of RAD140 in postmenopausal women with breast cancer (NCT03088527). ClinicalTrials.gov.
- National Library of Medicine. Phase 1/2 study to evaluate EP0062 as monotherapy and in combination in patients with advanced or metastatic AR+/HER-2-/ER+ breast cancer (NCT05573126). ClinicalTrials.gov.
- National Center for Biotechnology Information. PubChem compound summary for CID 44200882, RAD140 (vosilasarm). PubChem.
- Wagener F, Euler L, Görgens C, et al. Human in vivo metabolism and elimination behavior of micro-dosed selective androgen receptor modulator RAD140 for doping control purposes. Metabolites. 2022;12(7):666. PubMed.
- Brown AM, Ganjayi MS, Baumann CW. RAD140 (Testolone) negatively impacts skeletal muscle adaptation, frailty status and mortality risk in female mice. Clin Exp Pharmacol Physiol. 2023;50(12):973–983. PubMed.
- Heinze SS, Hodgins ML, Howlett SE. The impact of a selective androgen receptor modulator (RAD140) on frailty and underlying mechanisms in older male and female C57Bl/6 mice. Mech Ageing Dev. 2025;225:112054. PubMed.
- Barbara M, Dhingra S, Mindikoglu AL. Drug-induced liver injury associated with Alpha Bolic (RAD-140) and Alpha Elite (RAD-140 and LGD-4033). ACG Case Rep J. 2020;7(6):e00409. PubMed.
- Leung K, Yaramada P, Goyal P, et al. RAD-140 drug-induced liver injury. Ochsner J. 2022;22(4):361–365. PubMed.
- Perananthan V, George J. Severe liver injury following use of RAD-140, a selective androgen receptor modulator, for body building. Aust Prescr. 2024;47(1):26–28. PubMed.
- Dao D, King B, Dao H, Bahirwani R. Unregulated gains: a case of RAD-140-induced liver injury. Proc (Bayl Univ Med Cent). Published online July 8, 2026:1–3. PubMed.
- Vignali JD, Pak KC, Beverley HR, et al. Systematic review of safety of selective androgen receptor modulators in healthy adults: implications for recreational users. J Xenobiot. 2023;13(2):218–236. PubMed.
- Padappayil RP, Chandini Arjun A, Vivar Acosta J, et al. Acute myocarditis from the use of selective androgen receptor modulator (SARM) RAD-140 (Testolone). Cureus. 2022;14(1):e21663. PubMed.
- Schwartzman KH, Kohli U, Chaudhuri NR, Hoda M. Myopericarditis following use of selective androgen receptor modifier “RAD-140”. JACC Case Rep. 2024;29(15):102423. PubMed.
- Van Wagoner RM, Eichner A, Bhasin S, et al. Chemical composition and labeling of substances marketed as selective androgen receptor modulators and sold via the internet. JAMA. 2017;318(20):2004–2010. PubMed.
- Food and Drug Administration. Certain bodybuilding products put consumers at risk for heart attack, stroke, serious liver damage and more. Content current as of December 2, 2025. FDA.
- Food and Drug Administration. Warning letter to Atomix LLC, MARCS-CMS 719111. December 12, 2025. FDA.
- Drug Enforcement Administration, Diversion Control Division. Controlled substances, alphabetical order. August 27, 2026. DEA.
- World Anti-Doping Agency. The 2026 Prohibited List: International Standard. Effective January 1, 2026. WADA.