ACP-105 is a non-steroidal Selective Androgen Receptor Modulator (SARM) that was developed by Acadia Pharmaceuticals. It’s designed to deliver many of the anabolic (muscle-building) benefits of traditional androgens (like testosterone), without the typical androgenic side effects. While still experimental, ACP-105 has gained attention in the bodybuilding and athletic communities for its potential in lean muscle growth, bone density improvement, and neuroprotection.
Key Properties of ACP-105
| Characteristic | Value / Comment |
|---|---|
| Classification | SARM (Selective Androgen Receptor Modulator) |
| Chemical Name | Nonsteroidal SARM (no established IUPAC name publicly) |
| Molecular Formula | C₁₉H₁₄F₃N₃O₃ |
| Half-life | Approx. 4–6 hours (short, often dosed twice daily) |
| Anabolic Activity | High (comparable to testosterone in some studies) |
| Androgenic Activity | Low (minimal impact on prostate or hair loss) |
| Binding Affinity | High affinity for androgen receptors |
| Legal Status | Not approved for human use – research only |
| WADA Status | Prohibited in sport |
Effects and Benefits
1. Muscle Growth:
In animal studies, ACP-105 shows strong anabolic properties, supporting muscle hypertrophy even at low doses.
2. Bone Health:
It enhances bone mineral density, making it appealing for osteoporosis prevention or treatment.
3. Neuroprotection:
ACP-105 may offer protective benefits to brain tissue under oxidative stress—potentially useful for degenerative diseases (shown in preclinical studies).
4. Minimal Androgenic Side Effects:
Unlike testosterone, it does not significantly enlarge the prostate or promote hair loss, making it more tissue-selective.
Dosing for Research
- Common Dosing (bodybuilders): 5–10mg per day
- Cycle Length: 6–8 weeks
- Stacking: Often stacked with Ostarine (MK-2866) or LGD-4033 for recomposition
Note: These are anecdotal reports only—no human clinical data supports this usage.
Side Effects
- Mild suppression of natural testosterone (less than S23 or RAD-140)
- Possible fatigue or mood changes post-cycle
- Unknown long-term safety
Because of the short half-life, twice daily dosing may be required for stable plasma levels.
Post Cycle Therapy
PCT (Post Cycle Therapy) is recommended after using ACP-105, although the suppression it causes is considered mild to moderate compared to more potent SARMs like S23 or RAD-140.
Why PCT Is Needed After ACP-105
While ACP-105 doesn’t convert to oestrogen or DHT, it still binds strongly to androgen receptors, which can suppress your body’s natural testosterone production over time. Even if the suppression isn’t severe, it can cause:
- Low libido
- Fatigue
- Mood swings
- Loss of strength or muscle
Suggested PCT Options (Anecdotal Use)
| Option | Typical Dosage | Duration |
|---|---|---|
| Tamoxifen (Nolvadex) | 10–20mg/day | 4 weeks |
| Clomiphene (Clomid) | 25mg/day | 3–4 weeks |
| Natural Test Boosters | Optional support | During + after PCT |
For mild cycles of 5–10mg of ACP-105 over 6–8 weeks, some users report success with just Nolvadex at 10mg/day for 3–4 weeks.
Key Takeaways
- ACP-105 does not shut down testosterone completely—but it does suppress it.
- Skipping PCT could delay recovery and affect your gym performance and wellbeing.
- Always monitor symptoms post-cycle and consider bloodwork if possible.
Certainly! Here’s the FAQ about the SARM ACP-105, with all links removed:
FAQ: ACP-105 (SARM)
1. What is ACP‑105?
ACP‑105 is a non-steroidal selective androgen receptor modulator (SARM) originally developed by Acadia Pharmaceuticals. It selectively binds to androgen receptors, stimulating anabolic activity in muscle and bone tissue while avoiding many of the typical androgenic side effects associated with anabolic steroids.
2. How does it work?
ACP‑105 works as a partial agonist of the androgen receptor:
- It promotes muscle and bone growth without significantly affecting reproductive organs like the prostate.
- Unlike testosterone, it does not convert to estrogen, avoiding side effects such as gynecomastia and water retention.
- In lab studies, it showed anabolic activity comparable to testosterone, but with reduced androgenic properties, resulting in a favourable anabolic-to-androgenic ratio.
3. What benefits have been observed?
While human trials are lacking, studies in animals and anecdotal reports suggest:
- Increased lean muscle mass
- Improved bone density
- Enhanced endurance and stamina
- Preservation of muscle during physical stress (e.g. radiation)
- Potential cognitive benefits, including reduced anxiety and improved spatial memory
4. What is its toxicity and side effect profile?
ACP‑105 appears to have a lower risk of typical steroid-related side effects. However:
- Comprehensive safety data in humans is unavailable.
- Predictive modelling suggests potential risks such as organ toxicity, cardiotoxicity, and genotoxicity—particularly at higher doses or with long-term use.
- It may suppress natural testosterone production, requiring post-cycle therapy.
5. Is ACP‑105 approved for human use?
No. ACP‑105 is still considered an investigational compound and has not received regulatory approval for medical or clinical use in humans. Research has been limited to preclinical studies in animals.
6. What is a typical dosage?
In rodent studies, doses around 1 mg/kg were common. Extrapolated to humans, this would be roughly 10–12 mg per day for an average adult male. Anecdotally, users report taking 10–20 mg per day in 8–12 week cycles, although such use is not medically approved or standardised.
7. Does ACP‑105 suppress natural testosterone?
Yes. Like many SARMs, ACP‑105 can suppress the hypothalamic–pituitary–gonadal (HPG) axis, leading to reduced endogenous testosterone production. Users typically require a post-cycle therapy (PCT) to help restore hormone balance.
8. Is it banned in professional sports?
Yes. ACP‑105 is listed on the World Anti-Doping Agency (WADA) prohibited list. Athletes who test positive for it can face suspensions, disqualifications, or bans from competition.
9. What are the risks or unknowns?
- No human studies exist, so all data are extrapolated from animal trials and computational models.
- Long-term safety is unknown, particularly regarding heart, liver, and endocrine system effects.
- Products sold online as ACP‑105 are often unregulated and may contain impurities or incorrect dosages.
- Legal status varies by country and use may be restricted outside research settings.
10. Is ACP‑105 legal and safe to use?
ACP‑105 is not approved for human consumption and is considered a research chemical. Its sale for bodybuilding or recreational use is typically not legal. Even if available online, quality control and safety standards are highly questionable.
✅ Summary Table
| Category | Details |
|---|---|
| Type | SARM (Selective Androgen Receptor Modulator) |
| Function | Promotes muscle/bone growth, partial androgen receptor agonist |
| Benefits | Increased lean mass, endurance, bone strength, cognitive enhancement (preclinical) |
| Side Effects | Hormonal suppression, potential toxicity (unknown long-term effects) |
| Typical Dose (anecdotal) | 10–20 mg/day, 8–12 week cycle |
| Approval Status | Not approved for human use |
| WADA Status | Prohibited substance in competitive sports |
| Legal Status | Legal for research only in most regions |
Final Notes
ACP‑105 remains a promising but experimental compound. While it offers potential muscle and endurance benefits with fewer androgenic effects than steroids, the lack of human data presents a significant safety concern. Its use outside controlled research environments carries health, legal, and ethical risks.
