Commonly combined with RAD-140 (Testolone) in research protocols.
Ratings are based on published research data and are for informational purposes only.
RAD-140 demonstrates high anabolic potency with very low androgenic activity in preclinical models. A 2020 Phase I/II trial showed lean mass increases comparable to testosterone at significantly lower androgenic burden. It binds selectively to androgen receptors in muscle and bone tissue.
Research Post
RAD-140 (Testolone) is a non-steroidal Selective Androgen Receptor Modulator developed by Radius Health. Preclinical data positions it as one of the most potent and selective SARMs, with an anabolic-to-androgenic ratio significantly higher than testosterone in animal models.
RAD-140 binds to the androgen receptor with high affinity, inducing a conformational change distinct from that produced by testosterone or DHT. This unique receptor conformation differentially recruits co-activator proteins in muscle and bone versus androgenic tissues, producing tissue-selective anabolic activity. Importantly, RAD-140 is not a substrate for 5α-reductase and does not convert to DHT, nor is it aromatised to oestrogen.
Preclinical studies in non-human primates demonstrated a dose-dependent increase in lean body mass with minimal changes in prostate weight — in stark contrast to testosterone, which produced significant prostate enlargement at anabolic doses. RAD-140 also showed neuroprotective properties in vitro, activating cell survival pathways and reducing amyloid-beta toxicity.
RAD-140 entered human clinical trials as a potential treatment for AR/ER+ breast cancer. A 2020 Phase I/II trial published by Bardia et al. enrolled postmenopausal women with advanced breast cancer. The trial demonstrated disease control in a subset of patients, with an acceptable tolerability profile at doses of 50–150 mg/day — far higher than would be used in lean mass research protocols.
A Phase II trial (NCT04338360) investigating RAD-140 monotherapy in breast cancer was subsequently initiated. This trial provides the most detailed published human pharmacokinetic and safety data available for RAD-140. Preclinical primate data (Jones et al.) established the compound's anabolic potency and demonstrated testosterone suppression at higher doses, with recovery upon cessation.
RAD-150 (TLB-150) is a benzoate ester form of RAD-140. The ester modification significantly extends the effective half-life compared to RAD-140 (~16 hours), theoretically allowing less frequent administration in research protocols. Upon hydrolysis by plasma esterases, the active compound released is RAD-140 itself. Published clinical data specific to RAD-150 is very limited; most information derives from preclinical and informal research reports.
In preclinical models, RAD-140 demonstrates one of the highest anabolic-to-androgenic ratios of any SARM studied, with reported selectivity indices significantly exceeding those of LGD-4033 and Ostarine in some assays. However, direct head-to-head human clinical comparisons do not exist in published literature.
Yes. Preclinical primate studies and the clinical breast cancer trials both document testosterone suppression. Post-cycle support consideration is standard in research protocols involving RAD-140.
RAD-150 is an esterified prodrug form of RAD-140 with a longer half-life. Once cleaved by esterases, the active molecule is identical to RAD-140. The practical difference in research protocols is less frequent dosing frequency due to the extended half-life.
