What Is RAD-140?
RAD-140, commonly known as Testolone or RAD140, is a synthetic, nonsteroidal selective androgen receptor modulator. It was developed by Radius Health around 2010 as part of an effort to identify androgen-receptor ligands that could stimulate anabolic effects in muscle and bone without reproducing the full androgenic profile of testosterone or conventional anabolic steroids. Unlike testosterone, RAD-140 is not an esterified steroid hormone; it is a small-molecule compound that binds to the androgen receptor (AR). It has been investigated primarily in preclinical models and early oncology research rather than in an established program of approved human treatment.
Descriptions of RAD-140 often cite an anabolic-to-androgenic ratio of approximately 90:1. That number should be treated cautiously: it is a preclinical, assay-dependent comparison rather than a validated human clinical ratio, and results can vary according to the animal model, tissue tested, endpoint, dose, and comparator drug. RAD-140 is described as tissue-selective because AR signaling can differ between skeletal muscle, bone, prostate, skin, liver, and brain. Selectivity does not mean that adverse effects are absent or that the compound completely avoids androgen-sensitive tissues. RAD-140 remains research-only, is not an approved dietary supplement or medicine, and has no established safe or effective human dose.
Online bodybuilding discussions frequently present RAD-140 as a muscle-building alternative to anabolic steroids. Those claims substantially exceed the available evidence. There are limited human data, no broadly accepted therapeutic dosing protocol, and no reliable evidence establishing long-term cardiovascular, hepatic, reproductive, psychiatric, or cancer safety. A product labeled RAD-140 may also contain a different SARM, a steroid, an inactive substance, or an inaccurately measured amount. The regulatory status and legality of possession or sale vary by jurisdiction, and it is prohibited by the World Anti-Doping Agency.
Quick Reference
Member reference tables summarize the compound's research parameters.
Research Indications
Research Protocols
As reported in cited literature and research-community logs (see Research Citations below), not a personal dosing recommendation.
This member section describes parameters reported in the research literature.
Peptide Interactions
This member section summarizes reported compound interactions and evidence limitations.
Reported Research Time Points
This member section summarizes reported research time points.
Safety Notes
Included for harm-reduction awareness only, in the event this compound is encountered outside its labeled research use. Inclusion here does not imply RUO Codes endorses, recommends, or instructs human use.
This member section discusses research safety considerations and uncertainties.
Quality Indicators
Research Citations
- Selective androgen receptor modulator RAD140 is a potent neuroprotective agent with efficacy in rat models of neurodegeneration.
Jayakumar, A. R., et al., 2014, Endocrinology - The safety, pharmacokinetics, and effects of LGD-4033, a novel nonsteroidal oral selective androgen receptor modulator, in healthy young men: a randomized, double-blind, placebo-controlled, phase 1 study.
Basaria, S., et al., 2013, The Journals of Gerontology Series A - Adverse health consequences of performance-enhancing drugs: an endocrine society scientific statement.
Pope, H. G., Jr., et al., 2014, Current Opinion in Pharmacology - The effects of supraphysiologic doses of testosterone on muscle size and strength in normal men.
Bhasin, S., et al., 2001, Journal of Clinical Endocrinology & Metabolism - Selective androgen receptor modulators: a novel class of compounds for the treatment of muscle wasting and osteoporosis.
Narayanan, R., et al., 2018, Drugs