Overview

RAD-140 (Testolone) is a potent, orally bioavailable nonsteroidal SARM developed by Radius Health. It demonstrates one of the highest anabolic-to-androgenic ratios (90:1) of any known androgen receptor modulator, meaning it produces strong muscle anabolic effects while displaying minimal androgenic activity at the prostate in preclinical models. RAD-140 is also being investigated for neuroprotective properties and potential application in breast cancer treatment through its AR-agonist/ER-antagonist activity.

Mechanism of Action

RAD-140 binds to the androgen receptor (AR) with high affinity (Ki ~7 nM) and acts as a full agonist in muscle and bone tissue. The compound produces a distinct AR conformation that recruits anabolic coactivators preferentially over androgenic coactivators, achieving tissue selectivity. In the brain, RAD-140 activates AR-mediated neuroprotective pathways and has demonstrated apoptosis inhibition in neurons via stimulation of MAPK signaling and BDNF expression. Additionally, RAD-140 may act as an estrogen receptor (ER) antagonist in breast cancer cells expressing both AR and ER.

Potential Benefits

  • High anabolic potency with 90:1 anabolic:androgenic ratio in preclinical studies
  • Significant lean muscle mass increases in primate studies
  • Neuroprotective effects and BDNF upregulation
  • Potential activity against AR+/ER+ breast cancer
  • No conversion to estrogen or DHT (non-steroidal)
  • Oral bioavailability with once-daily dosing

Dosage Protocols

The following reflects doses used in published research studies. This is not medical advice. Consult a qualified healthcare professional.

Typical Range10-20 mg/day
Beginner10 mg/day
Intermediate15 mg/day
Advanced20 mg/day (some research protocols up to 30 mg but not recommended)
Cycle Duration6-8 weeks
Cycle Off8-12 weeks; post-cycle therapy required after most cycles

Long half-life (~60 hours) means steady-state is achieved within 2 weeks. More suppressive than Ostarine — post-cycle therapy with SERMs or peptides that support HPG axis (Kisspeptin, Gonadorelin) is strongly advisable.

Routes of Administration

Oral High

Good oral bioavailability; half-life ~60 hours allows once-daily dosing; no injection required

Stacking Protocols

Popular research stacks involving RAD-140 (Testolone):

Strength and Mass Stack

AR-driven muscle anabolism with GH/IGF-1 axis support

RAD-140 provides direct AR-mediated muscle growth; MK-677 adds GH elevation, appetite, and recovery support. Popular oral-only research stack.

Lean Gains Stack

Potent anabolic effect with fat oxidation and injury protection

RAD-140 builds muscle; Cardarine improves endurance and fat burning; Ostarine provides connective tissue and joint support.

Reconstitution

Typical Vial SizeN/A — oral capsules or liquid suspension (10-20mg/ml)
BAC WaterN/A — oral formulation
StorageStore at room temperature 15-25°C; protect from light and moisture
Shelf Life24-36 months sealed

Need exact syringe measurements?

Amino Acid Sequence

N/A — non-peptide small molecule SARM

Side Effects & Safety

  • Significant testosterone suppression (more pronounced than Ostarine)
  • Post-cycle therapy (PCT) strongly recommended
  • Possible hair loss (DHT-independent mechanism via AR activation in follicles)
  • Potential liver toxicity (case reports at high doses/long duration)
  • Aggression and mood changes reported at high doses

Synergistic Compounds

The following compounds have been studied alongside RAD-140 (Testolone) for potential complementary or synergistic effects:

Learn More

References & Further Reading

  • [object Object]
  • [object Object]