Peptides vs SARMs for Muscle Growth: Research Compounds Compared

Introduction: Two Distinct Classes of Research Compounds

The comparison between peptides and selective androgen receptor modulators (SARMs) represents one of the most fundamental questions in modern research compound pharmacology. Both classes have generated enormous interest among researchers studying muscle hypertrophy, recovery, and body composition, yet they operate through fundamentally different biological mechanisms with distinct safety profiles, regulatory statuses, and research applications.

Peptides are short chains of amino acids (typically 2-50 residues) that act as signaling molecules, interacting with specific receptors to modulate endogenous hormonal and regenerative pathways. SARMs are synthetic non-steroidal compounds designed to selectively activate androgen receptors in muscle and bone tissue while theoretically minimizing androgenic effects in reproductive organs. This selectivity promise has been central to their research interest, though the reality of tissue selectivity remains more nuanced than early marketing suggested.

This comprehensive comparison examines both compound classes across mechanisms of action, efficacy in muscle-related research, safety profiles, regulatory status, combinability, and practical research considerations. We draw on peer-reviewed literature, clinical trial data, and the broader pharmacological landscape to provide researchers with an evidence-based framework for understanding these two approaches.

Mechanism of Action: Fundamentally Different Pathways

How Peptides Promote Muscle Growth

Peptides relevant to muscle growth research operate through several distinct pathways, none of which involve direct androgen receptor activation. The primary mechanisms include growth hormone (GH) secretagogue activity, direct tissue repair signaling, and indirect anabolic effects through the GH/IGF-1 axis.

Growth hormone releasing peptides (GHRPs) like Ipamorelin bind to the ghrelin receptor (GHS-R1a), stimulating pulsatile GH release from the anterior pituitary. This GH then triggers hepatic IGF-1 production, which activates the PI3K/Akt/mTOR signaling cascade — the same pathway activated by insulin and mechanical loading during resistance training. The result is increased protein synthesis, satellite cell activation, and muscle fiber hypertrophy through a physiologically normal hormonal amplification rather than receptor-level manipulation.

GHRH analogs like CJC-1295 No DAC work upstream of GHRPs by binding GHRH receptors on somatotroph cells. When combined with Ipamorelin, the synergistic effect amplifies GH release 3-5 fold beyond either compound alone, as they activate complementary signaling pathways (Gs-cAMP for GHRH analogs, Gq-PLC for GHRPs). This combination approach mirrors the body’s natural dual-input GH regulation system.

Tissue-repair peptides like BPC-157 and TB-500 support muscle growth indirectly through enhanced recovery. BPC-157 upregulates growth factor receptors (VEGF, FGF, EGF), promotes angiogenesis, and accelerates tendon and ligament healing — all of which support more consistent training stimulus in preclinical models. TB-500 (thymosin beta-4 fragment) promotes actin polymerization, cell migration, and anti-inflammatory signaling, reducing recovery time between training bouts in animal studies.

How SARMs Promote Muscle Growth

SARMs operate through a fundamentally different mechanism: direct activation of the androgen receptor (AR), the same receptor targeted by testosterone, DHT, and anabolic steroids. The key theoretical advantage is tissue selectivity — SARMs were designed to preferentially activate AR in muscle and bone while producing minimal activation in prostate, sebaceous glands, and other androgen-sensitive tissues.

The most studied SARMs include RAD-140 (Testolone), LGD-4033 (Ligandrol), MK-2866 (Ostarine/Enobosarm), and S-23. These compounds bind the AR ligand-binding domain, inducing a conformational change that recruits coactivator proteins. The tissue selectivity hypothesis proposes that different AR conformations in different tissues recruit different coactivator/corepressor complexes, allowing selective transcriptional activation.

At the molecular level, SARM-bound AR activates androgen response elements (AREs) in gene promoters, upregulating genes involved in protein synthesis (MyoD, myogenin, MHC isoforms), satellite cell proliferation (Pax7), and nitrogen retention. This is a direct transcriptional effect — the compound enters the cell, binds a nuclear receptor, and directly alters gene expression. This contrasts sharply with peptides, which operate through cell-surface receptors and second messenger cascades.

Key Mechanistic Differences

The fundamental distinction is that peptides amplify the body’s own anabolic signaling (GH pulsatility, repair mechanisms, growth factor expression) while SARMs bypass endogenous regulation by directly activating androgen receptors. This has profound implications for both efficacy and safety that we examine throughout this article.

Peptides work within the body’s homeostatic feedback systems — pulsatile GH release is still subject to somatostatin negative feedback, and tissue repair peptides modulate rather than override inflammatory processes. SARMs, by contrast, activate AR independent of the hypothalamic-pituitary-gonadal (HPG) axis, which means they exert anabolic effects but also suppress endogenous testosterone production through negative feedback — a critical safety consideration we address in the safety section.

Efficacy in Muscle Growth Research

Peptide Evidence for Muscle Hypertrophy

The evidence base for peptide-mediated muscle growth comes primarily from GH/IGF-1 axis research. Elevated GH levels increase IGF-1 production, which has been extensively documented to promote muscle protein synthesis in both animal models and human clinical studies.

A landmark study by Rudman et al. (1990) in the New England Journal of Medicine demonstrated that 6 months of GH administration in elderly men increased lean body mass by 8.8% and decreased fat mass by 14.4%. While this used exogenous GH rather than secretagogues, it established the principle that GH/IGF-1 axis activation promotes favorable body composition changes.

More relevant to peptide research, studies on GHRP administration have shown significant GH elevation. Raun et al. (1998) demonstrated that ipamorelin produces dose-dependent GH release comparable to GHRH in preclinical models, with selectivity advantages over earlier GHRPs (no significant cortisol, prolactin, or ACTH stimulation). When combined with GHRH analogs like CJC-1295, the synergistic GH response creates sustained IGF-1 elevation that supports anabolic processes.

The tissue repair peptides contribute differently. BPC-157 research by Sikiric et al. has demonstrated accelerated healing of tendons, ligaments, muscles, and the GI tract in over 100 preclinical studies. For muscle growth specifically, the benefit is indirect: faster recovery means more frequent and intense training stimuli in research models, and prevention of overuse injuries that would otherwise interrupt progressive overload protocols.

TB-500’s role in muscle research centers on its ability to promote satellite cell differentiation and reduce fibrotic scar tissue formation after muscle injury. Goldstein et al. (2005) showed that thymosin beta-4 promoted cardiomyocyte survival and migration after myocardial injury, and subsequent research has explored similar regenerative mechanisms in skeletal muscle.

SARM Evidence for Muscle Hypertrophy

SARMs have a more direct evidence base for muscle hypertrophy, though the clinical trial landscape is less robust than often presented. The most extensive human data exists for Ostarine (MK-2866/Enobosarm).

Dalton et al. (2011) published Phase II results showing that Ostarine at 3 mg/day produced a 1.4 kg increase in lean body mass over 12 weeks in healthy elderly men and postmenopausal women, compared to placebo. The effect was dose-dependent, with the 3 mg dose outperforming both 0.1 mg and 0.3 mg doses. However, total body weight change was modest, and strength improvements were inconsistent across endpoints.

LGD-4033 (Ligandrol) was studied by Basaria et al. (2013) in a Phase I trial. Healthy young men receiving 1.0 mg/day for 21 days showed increased lean body mass (1.21 kg vs placebo) and decreased body fat. However, the study also documented dose-dependent suppression of total testosterone, sex hormone-binding globulin (SHBG), and free testosterone — confirming HPG axis suppression even at the lowest effective dose.

RAD-140 (Testolone) has the least human clinical data despite its popularity in research communities. A Phase I dose-escalation study (NCT03088527) was completed, but results have not been published in peer-reviewed literature as of early 2025. Most efficacy claims for RAD-140 derive from preclinical animal studies and anecdotal reports, making it the most data-poor of the commonly discussed SARMs.

Comparative Efficacy Assessment

Direct comparison is difficult because the compounds work through different mechanisms and timelines. SARMs produce more rapid and measurable lean mass gains (1-3 kg over 8-12 weeks in clinical studies) through direct AR activation. However, this comes with HPG axis suppression and the associated risks of testosterone decline.

Peptides produce more modest but sustainable changes through GH axis optimization. The typical expectation from a well-designed GH secretagogue protocol is improved body composition (reduced fat mass, modest lean mass increase) over 3-6 months, without the hormonal suppression seen with SARMs. The repair peptides (BPC-157, TB-500) don’t directly increase muscle mass but may support training consistency and recovery in research models.

The critical question for researchers is whether the faster, more pronounced muscle gains from SARMs justify the HPG suppression and regulatory uncertainty, compared to the more gradual, physiologically harmonious effects of peptide-based approaches.

Safety Profiles: Where the Comparison Becomes Critical

Peptide Safety Data

Growth hormone secretagogue peptides have a generally favorable safety profile in clinical research. Ipamorelin in particular has been studied for its selectivity — unlike earlier GHRPs (GHRP-2, GHRP-6), it does not significantly elevate cortisol, prolactin, or ACTH at GH-releasing doses (Raun et al., 1998). This selectivity makes it one of the cleanest GH-stimulating compounds available for research.

CJC-1295 (with DAC) was studied in clinical trials showing sustained GH and IGF-1 elevation over 6-14 days from a single injection. The no-DAC version used in research produces shorter pulses (2-3 hours) that more closely mimic physiological GH secretion patterns. Reported side effects in clinical studies included injection site reactions, water retention, and transient numbness/tingling — generally mild and self-limiting.

BPC-157 has an exceptional preclinical safety record. Sikiric et al. have published over two decades of animal studies with no reported organ toxicity, mutagenicity, or significant adverse effects. While comprehensive human clinical trial data is limited, the compound is derived from human gastric juice proteins (body protection compound), suggesting inherent biocompatibility. LD50 has not been established because lethal doses have not been reached in animal studies.

TB-500 (thymosin beta-4) has been studied in wound healing clinical trials (RegranEx) and cardiac repair studies with manageable safety profiles. The main theoretical concern is the promotion of angiogenesis in pre-existing tumors, though this has not been consistently demonstrated in clinical settings.

Overall, the peptide class does not suppress endogenous hormone production, does not cause hepatotoxicity, and does not produce the virilization or cardiovascular risks associated with androgenic compounds.

SARM Safety Concerns

The safety profile of SARMs is considerably more concerning than their marketing has traditionally suggested. The most significant and well-documented adverse effect is HPG axis suppression — the same issue that plagues anabolic steroids, though potentially to a lesser degree.

Basaria et al. (2013) documented that LGD-4033 at just 1.0 mg/day for 21 days suppressed total testosterone by 55%, free testosterone by approximately 40%, and SHBG by approximately 35%. FSH and LH also decreased, confirming central HPG suppression. Recovery after cessation took 35-56 days, during which subjects experienced a hypogonadal state. This is not a minor side effect — it represents significant endocrine disruption.

Hepatotoxicity is another documented concern. Several case reports have linked SARM use to drug-induced liver injury (DILI). Flores et al. (2020) published a case of severe cholestatic hepatitis associated with RAD-140, requiring hospitalization. Multiple similar cases have been reported to poison control centers. While the incidence is likely low, the severity can be significant, and the risk may be compounded by the widespread problem of product contamination and mislabeling in the SARM market.

Product quality represents a unique safety concern for SARMs. Van Wagoner et al. (2017) analyzed 44 SARM products purchased online and found that only 52% contained SARMs as labeled. Of those, 39% contained unapproved substances, 25% contained substances not listed on the label, and 9% contained no active compound at all. This contamination rate makes any risk-benefit analysis unreliable because researchers cannot be confident about what they are actually administering.

Cardiovascular concerns have also emerged. SARMs suppress HDL cholesterol (the “good” cholesterol), with LGD-4033 showing HDL reductions of up to 40% in clinical studies. This lipid perturbation, combined with unknown long-term effects on cardiac tissue, raises cardiovascular safety questions that remain unanswered due to the absence of long-term clinical trials.

Additional documented or theoretical concerns include: visual disturbances with S4 (Andarine), hair loss/thinning, acne (suggesting incomplete tissue selectivity), mood changes, and potential interference with natural puberty in younger subjects.

Safety Comparison Summary

The safety comparison strongly favors peptides. GH secretagogue peptides work within the body’s feedback systems, do not suppress endogenous testosterone, have no documented hepatotoxicity, and have decades of preclinical safety data. SARMs produce measurable endocrine disruption even at low doses, carry hepatotoxicity risk, face product quality/contamination issues, and lack long-term safety data from completed clinical trials. This safety differential is the single most important consideration for researchers choosing between these compound classes.

Regulatory Status and Legal Considerations

Peptide Regulatory Framework

Research peptides occupy a defined regulatory space. Many GH secretagogue peptides (tesamorelin, sermorelin) have FDA-approved pharmaceutical counterparts, providing a foundation of clinical safety data. Tesamorelin (Egrifta) is FDA-approved for HIV-associated lipodystrophy. Sermorelin was previously FDA-approved for GH deficiency diagnosis. This regulatory history provides confidence in the compound class, even when the specific research-grade versions are sold for investigational use.

BPC-157 and TB-500 are classified as research chemicals and are not FDA-approved for human use, but neither have they been subject to regulatory enforcement actions comparable to SARMs. The FDA has not issued public warnings specifically targeting peptide research suppliers operating within labeled research-use parameters.

Several peptides have active or completed clinical trials registered on ClinicalTrials.gov, indicating ongoing pharmaceutical interest and the potential for future regulatory approval pathways.

SARM Regulatory Status

SARMs occupy a much more precarious regulatory position. No SARM has received FDA approval for any indication. Ostarine (Enobosarm) came closest, with GTx Inc. completing Phase III trials for cancer-related cachexia, but the FDA declined approval in 2018 due to insufficient efficacy evidence and safety concerns. The company subsequently pivoted away from Enobosarm development.

In November 2019, the SARMs Control Act was introduced in the US Congress to classify SARMs as Schedule III controlled substances alongside anabolic steroids. While the act has not been passed as of early 2025, its introduction signals clear regulatory intent to restrict SARM access. Similar legislation exists in Australia, where SARMs are Schedule 4 prescription-only substances, and in the EU, where they are regulated as novel food ingredients or medicinal products depending on jurisdiction.

WADA (World Anti-Doping Agency) has included SARMs on its prohibited substances list since 2008, and multiple athletes have tested positive for SARM metabolites. The US Department of Defense has issued warnings to military personnel about SARM use. The FDA has issued multiple warning letters to companies marketing SARMs as dietary supplements, and the DOJ has prosecuted SARM sellers under the Designer Anabolic Steroid Control Act.

The regulatory trajectory for SARMs is clearly toward increased restriction, making them a less stable platform for long-term research programs.

Combinability and Stacking in Research

Peptide Stacking

Peptides offer exceptional combinability because different peptides target different receptors and pathways, producing synergistic rather than redundant effects. The most well-established peptide stack for muscle-related research is CJC-1295 No DAC + Ipamorelin, which synergistically amplifies GH release through dual-pathway activation (GHRH receptor + ghrelin receptor).

Adding BPC-157 and TB-500 to a GH secretagogue protocol creates a multi-pronged approach: enhanced GH pulsatility (CJC-1295 + Ipamorelin) plus accelerated tissue repair (BPC-157 + TB-500). The Wolverine Blend (BPC-157 + TB-500) exemplifies this stacking philosophy, combining two complementary repair peptides in a single formulation for research convenience.

Crucially, peptide stacking does not compound endocrine suppression risk. Adding BPC-157 to a CJC/Ipamorelin protocol does not increase HPG axis disruption because none of these compounds interact with the androgen receptor or suppress gonadotropin secretion. This additive efficacy without additive risk is a significant advantage of peptide-based research approaches.

SARM Stacking

SARM stacking (combining multiple SARMs simultaneously) is common in research communities but compounds the safety risks. Because all SARMs activate the androgen receptor, stacking produces additive HPG suppression — running RAD-140 + LGD-4033 simultaneously suppresses testosterone more than either alone. Similarly, hepatotoxicity risk and lipid perturbation increase with multiple AR-active compounds.

Some researchers combine SARMs with peptides, using peptides for recovery support while relying on SARMs for direct anabolic signaling. This hybrid approach acknowledges the complementary mechanisms, but the fundamental safety concerns with SARMs remain regardless of what they are combined with.

Post-cycle therapy (PCT) is universally recommended after SARM cycles to restore HPG axis function. The necessity of PCT highlights the disruptive nature of SARM use — no such recovery protocol is needed after peptide research cycles because peptides do not suppress the HPG axis in the first place.

Cost and Practical Research Considerations

From a practical standpoint, peptides and SARMs differ in administration, storage, and cost structure. Peptides are typically lyophilized powders requiring reconstitution with bacteriostatic water (BAC Water) and subcutaneous injection. They require refrigeration after reconstitution and have reconstituted stability of 2-4 weeks. SARMs are typically available as oral liquids or capsules, offering administration convenience.

However, the administration convenience of SARMs is offset by product quality concerns. As documented by Van Wagoner et al. (2017), the majority of SARM products do not contain what they claim. Peptide suppliers with third-party HPLC and mass spectrometry testing (such as Proxiva Labs) can provide verified purity certificates, and peptide identity is more reliably confirmed through standard analytical methods.

Cost comparison depends heavily on protocol duration and specific compounds. A 12-week GH secretagogue protocol (CJC-1295 + Ipamorelin) is typically comparable in cost to a 12-week SARM cycle. However, the peptide protocol does not require PCT drugs (additional cost for SARM users) and does not carry the risk of extended recovery periods that could necessitate medical intervention.

Research Applications: When Each Class Makes Sense

Peptides Are Better Suited For

Long-term body composition research: Because peptides do not suppress the HPG axis, they can be used for extended protocols (3-6+ months) without cycling off. This enables longitudinal studies that would be impractical with SARMs due to cumulative suppression and mandatory recovery periods.

Older subject research: Age-related GH decline (somatopause) makes GH secretagogues particularly relevant for aging research. The GH/IGF-1 axis naturally attenuates with age, and peptides can restore more youthful pulsatile GH patterns without introducing supraphysiological androgen receptor activation.

Injury recovery and rehabilitation: BPC-157 and TB-500 have specific tissue-repair applications that SARMs do not address. For researchers studying tendon, ligament, or muscle recovery, repair peptides offer mechanism-specific tools.

Combined benefit protocols: When the goal involves both GH optimization AND tissue repair, peptide stacking offers complementary pathways without compounding risk. The Wolverine Blend (BPC-157 + TB-500) plus CJC-1295/Ipamorelin addresses both axes simultaneously.

SARMs May Be Considered For

Short-term lean mass studies: When the specific research question requires rapid, measurable lean mass changes over 8-12 weeks, SARMs produce more dramatic short-term effects than peptides. However, this must be weighed against HPG suppression and recovery time.

Androgen receptor biology research: For researchers specifically studying AR-mediated transcription, tissue selectivity, or AR conformational biology, SARMs are the appropriate tool as this is their specific mechanism of action.

Oral administration requirement: If a research protocol requires oral-only administration, SARMs offer this advantage. However, oral peptide delivery systems are an active area of pharmaceutical development that may eliminate this distinction.

The Trend Toward Peptides in Modern Research

The research landscape has shifted significantly toward peptides over the past 5 years. Several factors drive this trend:

Failed SARM clinical programs: The Enobosarm FDA rejection in 2018 and the subsequent collapse of GTx Inc. (rebranded as Oncternal Therapeutics, pivoting away from SARMs entirely) signaled that the SARM pharmaceutical pathway may be a dead end. No SARM has advanced past Phase III since then.

Improved peptide production: Advances in solid-phase peptide synthesis (SPPS) have reduced costs and improved purity. Research-grade peptides with >99% purity are now widely available, with reliable third-party testing infrastructure.

GLP-1 agonist success: The spectacular clinical success of semaglutide (Ozempic/Wegovy) — a peptide — has validated the peptide therapeutic paradigm and accelerated investment in peptide research broadly. This success has created positive regulatory momentum for the entire peptide class.

Growing safety evidence for peptides: Decades of preclinical BPC-157 research, clinical tesamorelin trials, and the growing body of CJC-1295/Ipamorelin data have built a compelling safety case for peptides that SARMs cannot match.

Regulatory direction: With SARMs Control Act legislation pending and multiple FDA enforcement actions against SARM sellers, the regulatory trend clearly disfavors SARMs. Peptides, by contrast, are experiencing increased pharmaceutical investment and clinical trial activity.

Comparison Table: Peptides vs SARMs for Muscle Research

Parameter	Peptides (GH Secretagogues)	SARMs
Primary Mechanism	GH/IGF-1 axis amplification	Direct androgen receptor activation
Onset of Effects	2-4 weeks (body composition); immediate GH pulse	1-2 weeks (strength); 4-6 weeks (lean mass)
Lean Mass Gain (12 weeks)	Modest (1-3 kg via GH optimization)	Moderate (2-4 kg via AR activation)
Fat Loss	Significant (GH-mediated lipolysis)	Mild (secondary to increased muscle mass)
HPG Axis Suppression	None	Significant (40-60% T reduction at low doses)
Hepatotoxicity	Not documented	Case reports of DILI (RAD-140, LGD-4033)
PCT Required	No	Yes (4-8 weeks recovery)
Lipid Impact	Neutral to mildly positive	HDL suppression (up to 40%)
Product Purity Reliability	High (HPLC/MS verifiable)	Low (52% accuracy per Van Wagoner 2017)
Regulatory Direction	Positive (pharma investment growing)	Negative (SARMs Control Act pending)
Combinability	Excellent (non-overlapping pathways)	Risky (additive suppression)
Long-term Use Feasibility	High (no cycling required)	Low (8-12 week max, then PCT)
Administration	Subcutaneous injection	Oral (liquid/capsule)
FDA-Approved Compounds in Class	Yes (Tesamorelin, Semaglutide, etc.)	None

Frequently Asked Questions

Can peptides and SARMs be used together in research?

Mechanistically, peptides and SARMs target different receptors and could theoretically be combined. Some research protocols pair BPC-157 with SARMs for recovery support. However, combining them does not eliminate SARM-specific risks (HPG suppression, hepatotoxicity, product quality concerns). Many researchers have moved toward peptide-only protocols to avoid these risks entirely.

Which produces faster visible results?

SARMs typically produce faster scale weight and strength changes (2-4 weeks for noticeable effects). Peptide effects are more gradual, with body composition changes becoming apparent over 4-8 weeks. However, SARM “fast results” are partly attributable to water retention and glycogen loading from AR activation, which reverse upon cessation. Peptide-mediated changes tend to be more durable because they result from actual fat loss (GH-mediated lipolysis) rather than temporary fluid shifts.

Do SARMs require post-cycle therapy?

Yes. All SARMs studied in clinical trials have demonstrated dose-dependent HPG axis suppression. Recovery of natural testosterone production after a SARM cycle takes 4-8 weeks and may require pharmaceutical intervention (SERMs like tamoxifen or clomiphene) in cases of significant suppression. Peptides do not require PCT because they do not suppress the HPG axis.

Are peptides legal?

Research peptides are legal to purchase and possess for research purposes in most jurisdictions. Several peptides have FDA-approved pharmaceutical counterparts (tesamorelin, semaglutide, sermorelin), confirming the safety and legitimacy of the compound class. SARMs face increasing regulatory pressure and may become controlled substances in the near future.

Conclusion: The Evidence Favors Peptides for Most Research Applications

The peptides vs SARMs comparison reveals a clear differential in the risk-benefit calculus. SARMs offer faster, more pronounced lean mass gains through direct androgen receptor activation, but this comes at the cost of HPG axis suppression, hepatotoxicity risk, lipid perturbation, product quality uncertainty, and a deteriorating regulatory landscape.

Peptides offer a safer, more physiologically harmonious approach to muscle growth research. GH secretagogues like CJC-1295 No DAC and Ipamorelin amplify natural GH pulsatility without endocrine disruption. Tissue repair peptides like BPC-157 and TB-500 support recovery through specific regenerative mechanisms. These compounds can be combined freely without compounding risk, used for extended protocols without cycling, and sourced with reliable purity verification.

For researchers prioritizing long-term safety, regulatory stability, and mechanistic elegance, peptides represent the superior platform for muscle growth and body composition research. The pharmaceutical industry appears to agree — peptide investment is booming while SARM clinical programs have largely been abandoned.

Visit Proxiva Labs for third-party tested research peptides including CJC-1295 No DAC, Ipamorelin, BPC-157, and TB-500.

References

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3. Sikiric P, et al. Stable gastric pentadecapeptide BPC 157: novel therapy in gastrointestinal tract. Curr Pharm Des. 2011;17(16):1612-1632.
4. Goldstein AL, et al. Thymosin beta4: a multi-functional regenerative peptide. Expert Opin Biol Ther. 2005;5(9):1225-1234.
5. Dalton JT, et al. The selective androgen receptor modulator GTx-024 (enobosarm) improves lean body mass and physical function in healthy elderly men and postmenopausal women: results of a double-blind, placebo-controlled phase II trial. J Cachexia Sarcopenia Muscle. 2011;2(3):153-161.
6. Basaria S, et al. The safety, pharmacokinetics, and effects of LGD-4033, a novel nonsteroidal oral, selective androgen receptor modulator, in healthy young men. J Gerontol A Biol Sci Med Sci. 2013;68(1):87-95.
7. Van Wagoner RM, et al. Chemical composition and labeling of substances marketed as selective androgen receptor modulators and sold via the internet. JAMA. 2017;318(20):2004-2010.
8. Flores JE, et al. Severe cholestatic hepatitis from RAD-140 (Testolone): a case report. ACG Case Rep J. 2020;7(8):e00455.
9. Teichman SL, et al. Prolonged stimulation of growth hormone (GH) and insulin-like growth factor I secretion by CJC-1295, a long-acting analog of GH-releasing hormone, in healthy adults. J Clin Endocrinol Metab. 2006;91(3):799-805.
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This article is for educational and research purposes only. Not intended as medical advice. All compounds discussed are for laboratory research use. Visit Proxiva Labs for verified research peptides.