RAD140 (Vosilasarm) (also known as RAD140 or EP0062 or Vosilasarm) is a performance-enhancing peptide studied for its effects on sarm, muscle gain, breast cancer. SARM (RAD140) for breast cancer trials. Tissue-selective AR modulator. Liver toxicity risk, testosterone suppression. Not FDA-approved, banned in sports.
Vosilasarm (RAD140/EP0062) is a selective androgen receptor modulator (SARM) originally developed by Radius Health, now under development by Ellipses Pharma for hormone-sensitive breast cancer (AR+/ER+/HER2-). Potent, orally-active, nonsteroidal SARM with high androgen receptor affinity (Ki = 7 nM vs 29 nM for testosterone). Exhibits tissue-selective activity: acts as agonist in skeletal muscle and bone (anabolic effects), but antagonist in prostate and breasts (blocking AR activation and cellular proliferation).
Overview
EP0062 reformulation shows markedly improved bioavailability versus original RAD140.
Clinical trials in breast cancer demonstrated 58% stable disease rate and 21% clinical benefit rate at ≥6 months, with marked CA15-3 suppression in 26% of heavily pre-treated patients.
Maximum tolerated dose 100mg daily, with 10mg BID selected as optimal Phase 2 dose.
Originally developed for sarcopenia, osteoporosis, and cancer cachexia but development discontinued for these indications.
Preclinical data showed 90% anabolic potency of testosterone and >10% weight gain in 28 days at 0.1mg/kg in primates.
Concerning safety profile includes documented liver toxicity cases, elevated liver enzymes, 50% testosterone suppression in primates, and negative impacts on skeletal muscle adaptation, frailty, and mortality risk in animal studies.
Not FDA-approved; investigational use only in clinical trials.
Banned by WADA and illegal for non-medical use in many jurisdictions.
Black market products (5-30mg daily doses) pose significant health risks with unknown purity and contaminants.
Mechanism of action
Activates androgen receptors in muscle and bone while blocking them in prostate and breast tissue. Investigational for breast cancer; not FDA-approved. Liver toxicity and testosterone suppression reported.
Reported effects
Effects reported in the literature and from preclinical models include:
- RAD140 is a selective androgen receptor modulator that produces anabolic effects within skeletal muscle, which led researchers to test it against sarcopenia. [1] Preclinical
- Ten weeks of RAD140 at 5 mg/kg failed to improve strength and increased frailty status and mortality risk in young and adult female mice. [1] Preclinical
- RAD140 decreased adaptive potential to repeated eccentric contractions in young female mice, with no torque difference between groups after 2-3 weeks of recovery. [1] Preclinical
- A deep-learning drug-target screen prioritized vosilasarm among 12 candidate compounds with high predicted binding affinity to gynecomastia-associated genes such as AR and IGF1, pending experimental validation. [2] Preclinical
Evidence grades: FDA approvedApproved (non-US)Phase IIIPhase IIPhase IPreclinicalAnecdotal
Dosage and administration
General
- Clinical trials (breast cancer): 50-150mg daily oral
- Phase 2 recommended dose: 10mg twice daily (20mg total)
- Black market use (not recommended): 5-30mg daily
- Clinical dosing should only be under medical supervision
- Liver function monitoring required during use
Maximum tolerated dose
- 100mg daily
Note
- Non-medical use is illegal and dangerous
Natty status
RAD140 (Vosilasarm) is classified as not natty. It appears on the WADA prohibited list and is banned by major natural bodybuilding federations.[3] Use of this compound places the athlete in the enhanced category rather than the natural category in competitive contexts.
Research
The peptide has been the subject of 7 studies and reference works collected on this site. Additional bibliography is in § External links below.
Related compounds
Other peptides in this catalogue with overlapping mechanisms or status:
References
- a b c Negative muscle effects in mice study
- ^ Deep Learning-Based Drug Compounds Discovery for Gynecomastia. Recent
- a b World Anti-Doping Agency. (2026). Prohibited List 2026.
External links
- Wikipedia article
- Breast cancer phase 1/2 trial
- Liver toxicity case reports
- Mechanism and preclinical data
- Breast cancer mechanism research
This page was last updated on August 4, 2026, at 00:46 (UTC).
Research last reviewed on August 4, 2026.
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