ACP-105 SARM Guide
A selective androgen receptor modulator developed by Acadia Pharmaceuticals for potential treatment of muscle wasting and osteoporosis. Complete analysis of mechanisms, benefits, risks, and research status.
What is ACP-105?
ACP-105 is a non-steroidal selective androgen receptor modulator (SARM) discovered in 2009 by researchers at Acadia Pharmaceuticals Inc. [^54^] It acts as a partial agonist at the androgen receptor, demonstrating anabolic effects on muscle and bone tissues while exhibiting tissue selectivity to minimize prostate-related side effects associated with traditional testosterone therapies. [^54^]
Unlike traditional anabolic steroids, SARMs like ACP-105 were designed to target androgen receptors in specific tissues—primarily muscle and bone—while sparing organs like the prostate. This selectivity aims to provide the muscle-building benefits of androgens without many of the unwanted androgenic side effects. [^54^]
Chemical Profile
- CAS Number: 899821-23-9 (also reported as 1048998-11-3) [^54^][^58^]
- Class: Non-steroidal SARM with bicyclic amine core [^54^]
- Administration: Oral (high gastrointestinal absorption predicted) [^58^]
- Half-Life: ~30 hours (animal models); ~1.18h in silico prediction [^54^][^58^]
- Metabolism: Primarily CYP3A4, with contributions from CYP2C9, CYP2C19 [^58^]
Research Status & Development
Preclinical Only|No Human Clinical Trials
Acadia Pharmaceuticals nominated ACP-105 as a development candidate in February 2006, following promising preclinical results demonstrating tissue-selective anabolic effects with minimal prostate impact. [^61^] However, as of 2024, no Investigational New Drug (IND) application has been filed with the FDA, and no Phase I, II, or III clinical trials are registered on ClinicalTrials.gov. [^54^]
Preclinical Findings
- • Reversed testosterone deficiency markers in castrated rats [^54^]
- • Improved rotorod performance in irradiated mice [^55^]
- • Enhanced fear conditioning (hippocampus-independent memory) [^55^]
- • Reduced anxiety-like behaviors in Alzheimer's mouse models [^54^]
Current Usage
- • Research tool in academic studies [^54^]
- • Anti-doping detection method development [^54^][^59^]
- • Metabolite identification for forensic testing [^58^]
- • NOT approved for human consumption [^54^]
Critical Research Gap
All safety and efficacy data for ACP-105 are derived from preclinical animal studies only. No human clinical data exists to assess long-term risks, proper dosing, or efficacy in humans as of 2024. [^54^] The compound is not listed in Acadia's current product pipeline, suggesting the program may have been deprioritized or halted. [^54^]
Mechanism of Action
ACP-105 functions as a partial agonist at androgen receptors (AR), distinguishing it from full agonists like testosterone. This partial activation provides a nuanced modulation of receptor activity that promotes anabolic effects in muscle and bone while limiting full activation in androgen-sensitive tissues like the prostate. [^54^]
Key Mechanisms
- 1.Selective AR Binding: High affinity for muscle and bone ARs
- 2.Partial Agonism: Activates anabolic pathways without full androgenic stimulation
- 3.Neuroprotection: Upregulates AR expression in hippocampus [^54^]
- 4.Metabolic Modulation: Increases amyloid-β degrading enzymes (neprilysin, IDE) [^54^]
Pharmacokinetic Profile (In Silico)
Source: ADME profiling using 7 independent computational methods [^58^]
Potential Benefits (Preclinical)
Muscle Growth
Moderate Anabolic EffectReversed endocrine markers of muscle loss and improved anabolic parameters in castrated rat models over 2 weeks [^54^]
Bone Health
Osteo-anabolicRestored bone-related markers of testosterone deficiency with minimal prostate stimulation in animal models [^54^]
Cognitive Function
NeuroprotectiveEnhanced fear conditioning and reduced radiation-induced sensorimotor deficits in mice; improved spatial memory in Alzheimer's models [^54^][^55^]
Motor Performance
Sensorimotor SupportImproved rotorod performance in irradiated female mice, suggesting potential for muscle coordination preservation [^55^]
Anxiety Reduction
Anxiolytic (in combo)Decreased anxiety-like behaviors in gonadectomized male 3xTg-AD mice when combined with AC-186 [^54^]
Prostate Safety
Tissue SelectiveDemonstrated tissue specificity with little effect on prostate compared to full androgens in preclinical testing [^54^][^61^]
⚠️ Important Limitation
All listed benefits are derived from animal studies only. No human clinical trials have verified these effects in people. Efficacy and safety in humans remain unknown.
Dosage & Administration
| Protocol | Dose | Duration | Notes |
|---|---|---|---|
| Animal Research | 1 mg/kg/day (mice, subcutaneous) [^55^] | Variable (up to 7 months in some studies) | Preclinical only |
| ⚠️ Unverified Human Protocols | 10-20 mg/day (oral) | 8-12 weeks | NO CLINICAL DATA |
| Half-Life Consideration | ~30 hours (animal models) | Once daily dosing theoretically possible | In silico prediction: ~1.18h [^58^] |
No Established Human Dose
There is NO safe or established dosage for human consumption. Any dosing protocols found online are based on anecdotal reports, not clinical data. The only published research uses animal models with different metabolic parameters than humans.
Side Effects & Risks
Observed in Preclinical Studies
- •Transient liver enzyme elevations: ALT and AST increased at high doses (>20 mg/kg) in rats, resolving post-treatment [^54^]
- •Mild androgenic effects: Some virilization potential, though less than full androgens [^54^]
- •Hormonal suppression: Expected testosterone suppression via negative feedback (AR agonist mechanism) [^56^]
Theoretical Human Risks
- •Testosterone Suppression: Will suppress natural testosterone production requiring PCT [^56^]
- •Liver Toxicity: Hepatotoxicity observed with other SARMs (LGD-4033, RAD-140) in case reports [^62^]
- •Cardiovascular: Lipid profile disruption (decreased HDL) seen with SARMs [^62^]
- •Unknown Long-term: No data on cancer risk, fertility, or organ damage [^54^]
SARM Class Safety Concerns (2022 Systematic Review)
A comprehensive review of SARM safety in healthy adults found frequent adverse effects including: [^62^]
Hepatotoxicity
Cholestatic hepatitis, jaundice, elevated liver enzymes
Hormonal Disruption
Testosterone suppression, decreased testes size, mood swings
Lipid Abnormalities
Decreased HDL cholesterol
Acne & Skin
Androgenic skin effects
ACP-105 vs. Other SARMs
| SARM | Potency | Suppression | Research Status | Best For |
|---|---|---|---|---|
| ACP-105 | MODERATE | Mild (expected) | Preclinical only [^54^] | Research, potential neuroprotection |
| Ostarine (MK-2866) | MILD | Mild-Moderate | Phase III clinical trials [^54^] | Beginners, muscle preservation |
| RAD-140 | HIGH | Moderate-Severe [^52^] | Phase I trials | Experienced users, breast cancer research |
| LGD-4033 | HIGH | Moderate-Severe [^52^] | Phase II trials | Muscle wasting conditions |
| AC-262 | MODERATE | Mild (expected) | Preclinical [^52^] | Research, Alzheimer's studies |
Key Takeaway: ACP-105 is considered a moderate potency SARM with potentially fewer side effects than RAD-140 or LGD-4033, but this is based on preclinical data only. [^52^] It has not advanced to human trials unlike Ostarine (MK-2866).
Legal Status & Doping
Regulatory Status
- •NOT FDA approved for human consumption [^54^]
- •Research chemical only status in most countries
- •WADA Prohibited: Banned by World Anti-Doping Agency [^54^]
- •Detectable in urine and hair testing [^60^]
Detection Methods
Advanced analytical methods can detect ACP-105 and its metabolites: [^58^][^59^][^60^]
- • UHPLC-MS/MS in urine and hair
- • 12 metabolites identified (M1-M6 primary)
- • CYP3A4-mediated metabolism markers
- • Detection windows vary by tissue type
Frequently Asked Questions
Is ACP-105 safe for human use?
No. ACP-105 has never been tested in human clinical trials. All safety data comes from animal studies. Long-term effects in humans are completely unknown. [^54^]
Does ACP-105 suppress testosterone?
Yes, as an androgen receptor agonist, ACP-105 is expected to suppress natural testosterone production through negative feedback, though the degree is unquantified in humans. Post-cycle therapy (PCT) is theoretically recommended. [^56^]
How does ACP-105 compare to RAD-140?
ACP-105 is significantly less potent than RAD-140 based on preclinical data. RAD-140 has stronger anabolic effects but also greater suppression and androgenic side effects. [^52^][^53^]
Can ACP-105 be detected in drug tests?
Yes. ACP-105 is detectable in urine and hair samples using UHPLC-MS/MS methods. It is prohibited by WADA and tested for in anti-doping protocols. [^54^][^60^]
Bottom Line
ACP-105 is a preclinical research compound with no human safety or efficacy data. While it showed promise in animal models for muscle preservation, bone health, and cognitive function, it has not advanced to clinical trials and is not approved for human consumption. [^54^]
The compound is banned by WADA and detectable in drug testing. Individuals considering SARMs for performance enhancement should understand that all SARMs carry risks of testosterone suppression, liver toxicity, and unknown long-term effects based on case reports with similar compounds. [^62^]
⚠️ This guide is for educational purposes only. We do not recommend or endorse the use of research chemicals for human consumption. Always consult qualified healthcare professionals for medical advice.
Sources & References
[54] Grokipedia - ACP-105 Medical Research & Development Status
[55] ScienceDirect - Effects of ACP-105 on Motor Performance (2011)
[58] PMC - First Multifaceted ADME Profile of ACP-105 (2023)
[59] MDPI - Investigation of ACP-105 Metabolites for Doping Control (2021)
[60] ScienceDirect - SARMs Screening in Hair Using UHPLC-MS/MS (2022)
[61] Acadia Pharmaceuticals - ACP-105 Development Candidate Nomination (2006)
[62] PMC - Systematic Review of SARM Safety in Healthy Adults (2022)
[56] Pumping Iron Store - Safest SARMs Guide (2024)
Repxx Research Team
Evidence-based fitness and supplement education
Medical Disclaimer
This guide is for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment. ACP-105 is not approved for human consumption. The information provided is based on preclinical animal studies and should not be interpreted as evidence of safety or efficacy in humans. Always consult qualified healthcare professionals before using any research compounds. We do not endorse the use of unapproved substances.
Last Updated: January 2024 | Reviewed by qualified research analysts