RAD 140 (Testolone)
A potent selective androgen receptor modulator known for its strong anabolic effects on muscle and bone with a favorable safety profile compared to steroids.
Common Dosage
10mg - 20mg daily (oral) for 8-12 weeks
Category
SARM
- Significant muscle gain
- Strength increase
- Fat loss
- Neuroprotection
RAD 140 (Testolone) was developed by Radius Health Inc. for potential use in breast cancer treatment and muscle wasting conditions. It is considered one of the most potent SARMs, with a high anabolic-to-androgenic ratio (greater than testosterone in preclinical models). Clinical trials in ER+/PR+ metastatic breast cancer (as a non-steroidal anti-estrogen / androgen receptor modulator) were conducted, producing some clinical data. Its potency has made it one of the most widely used SARMs in the performance enhancement community despite limited safety data.
RAD 140 binds to the androgen receptor with high affinity and selectivity, producing anabolic effects in muscle and bone while minimizing androgenic activity in prostate and other androgen-sensitive tissues. In addition to anabolic AR activation, it exhibits neuroprotective properties — reducing amyloid-beta toxicity in neural tissue through AR-mediated pathways — making it the subject of interest in neurological research beyond its muscle-building applications.
- Breast cancer — ER+/PR+ metastatic breast cancer trials (AR-positive subtype)
- Muscle wasting and sarcopenia research
- Lean mass development in hypogonadism
- Neuroprotection research — amyloid-beta toxicity reduction
- Strength and power development
Breast Cancer Clinical Trial
Early phase breast cancer trials with RAD 140 showed clinical benefit rate of approximately 30% in heavily pretreated ER+/AR+ metastatic breast cancer patients — providing some clinical validation for its AR modulatory activity in a human cancer setting.
Neuroprotection Mechanism
Laboratory research demonstrated that RAD 140 activates AR in neurons to trigger anti-apoptotic MAPK signaling, protecting neurons from amyloid-beta and kainate toxicity in Alzheimer's and epilepsy models — an unexpected neuroprotective dimension to a primarily anabolic SARM.
Performance Community Outcomes
RAD 140 is consistently reported as the most powerful SARM for lean mass gain — users commonly report 5–10 lbs of lean muscle gain in 8–12 week cycles at 10–20mg, with significant strength increases, though post-cycle suppression is also consistently noted as significant.
- Testosterone suppression is significant and dose-dependent — post-cycle therapy (PCT) with SERMs is generally required
- Hair shedding and androgenic alopecia acceleration are commonly reported — the selectivity is not absolute for androgen-sensitive hair follicles
- Liver stress — elevated liver enzymes are documented in users; periodic liver function testing during use is strongly advised
- Aggression and mood changes with higher doses
- WADA-prohibited substance — relevant for competitive athletes
- Long-term safety is entirely unknown
- SARMs are increasingly under regulatory scrutiny — legal status varies by country
- Testosterone suppression
- Hair shedding
- Aggression
- Liver stress