Review
This narrative review examines the pharmacological mechanisms, safety profiles, and regulatory status of twelve peptides commonly marketed in sports medicine contexts, spanning both FDA-approved compounds (e.g., tesamorelin/Egrifta) and unapproved "gray market" substances (e.g., BPC-157, CJC-1295, TB-500, ipamorelin, and others). The authors note that while many unapproved peptides show promising tissue repair and metabolic effects in animal models, rigorous human safety and efficacy data are largely absent. The review highlights a growing direct-to-consumer gray market operating outside regulatory oversight and discusses the potential for serious patient harm. Notably, the authors address the placebo effect as a possible mediator of perceived peptide efficacy and examine how social media may amplify this effect. A clinician-oriented framework is proposed to guide evidence-based patient discussions about peptide use for musculoskeletal healing and athletic performance, including consideration of alternative treatments. Key limitations include the narrative (non-systematic) review methodology and the inherently limited and heterogeneous evidence base for most compounds discussed, particularly in human populations.
Sports medicine (Auckland, N.Z.) · Apr 2026DOI ↗ ReviewPreprint
This narrative review examines the pharmacological mechanisms, safety profiles, and regulatory status of twelve peptides commonly encountered in sports medicine and athletic performance contexts, including both approved agents (e.g., tesamorelin/Egrifta, sermorelin) and unapproved "gray market" compounds (e.g., BPC-157, CJC-1295, TB-500, ipamorelin, AOD-9604, FS-344, GHK-Cu, MOTS-C, SS-31, and thymosin beta-4). The authors note that while many unapproved peptides show promising tissue repair and metabolic outcomes in animal models, rigorous human safety and efficacy data remain scarce. The review highlights the emergence of a direct-to-consumer gray market operating outside regulatory oversight and the potential for serious patient harm. It further discusses the placebo effect as a potential mediator of perceived peptide efficacy, and how social media may amplify this effect. The authors provide a clinical framework to guide patient-provider discussions and promote evidence-based practice for musculoskeletal healing. Key limitations include the narrative (non-systematic) review design, reliance on preclinical literature for most unapproved compounds, and the absence of head-to-head human trials for the majority of agents discussed.
Unknown journal · Apr 2026DOI ↗ Review
This narrative review examines the potential role of therapeutic peptides in orthopaedic care, synthesizing preclinical and mechanistic literature across several peptide classes. The authors categorize peptides by their primary proposed function: wound-healing agents (BPC-157, TB-500, GHK-Cu), growth hormone secretagogues (ipamorelin, CJC-1295, tesamorelin, sermorelin, AOD-9604), recovery-enhancing peptides (epithalon, delta sleep-inducing peptide, pinealon), and neuroactive peptides (selank, semax, dihexa). The review describes how these compounds are theorized to interact with signaling pathways—including PI3K/Akt, mTOR, MAPK, TGF-β, and AMPK—to promote tissue regeneration, resolve inflammation, and support neuromuscular recovery. The authors acknowledge that, while preclinical evidence is promising, robust human clinical trial data are largely absent, representing a significant gap in the literature. Limitations include the review's reliance on animal and in vitro studies, the absence of a systematic search methodology, and the lack of direct clinical evidence supporting efficacy or safety in human orthopaedic populations. The authors call for future controlled trials to validate these mechanistic findings in clinical settings.
Journal of the American Academy of Orthopaedic Surgeons. Global research & reviews · Jan 2026DOI ↗ ReviewPreprint
This review paper examines the pharmacological mechanisms, safety profiles, and regulatory status of both approved and unapproved peptide therapies relevant to sports medicine, musculoskeletal injury recovery, and athletic performance enhancement. The compounds reviewed span a wide spectrum — from FDA-approved agents such as tesamorelin and sermorelin, to gray-market compounds including BPC-157, TB-500, CJC-1295, Ipamorelin, AOD-9604, FS-344, GHK-Cu, MOTS-C, and SS-31. The authors note that while many unapproved peptides show promising results in preclinical and animal models — including favorable tissue repair and metabolic effects — rigorous human safety and efficacy data remain scarce. The review highlights a growing direct-to-consumer gray market operating outside regulatory oversight and discusses how social media may amplify perceived benefits through placebo-related mechanisms. The paper also offers a clinical framework to guide patient conversations and support evidence-based decision-making. Key limitations include the inherent constraints of a narrative review design, reliance on heterogeneous preclinical data for unapproved compounds, and the absence of controlled human trials for most of the highlighted peptides.
Unknown journal · Dec 2025DOI ↗ Limited · human
This study developed and validated an analytical method for detecting a broad panel of 18 performance-enhancing peptides (molecular weight <2 kDa) in human urine, as defined by the World Anti-Doping Agency (WADA) prohibited list. The method uses direct urine injection—bypassing complex sample preparation—coupled with liquid chromatography and ion mobility time-of-flight mass spectrometry (IM-TOFMS). The researchers reported limits of detection (LOD) ranging from 50 to 500 pg/mL, well below WADA's minimum required performance level of 2 ng/mL. The method demonstrated acceptable precision (imprecision <20%) and linearity across a 0–10 ng/mL working range. Stability testing identified –20°C as the appropriate storage temperature for urine samples. As a proof-of-concept, the method was applied to real elimination study urine samples from individuals who had administered GHRP-2, GHRP-6, or LHRH, successfully detecting these compounds. Key limitations include the small number of human subjects used in the elimination studies, which were primarily intended to demonstrate analytical feasibility rather than investigate pharmacokinetics or clinical effects. The study is a methodological/analytical validation paper focused on anti-doping screening, not a clinical or therapeutic investigation.
Journal of separation science · Dec 2015DOI ↗ Animal only
This study investigated the effects of intra-articular injections of AOD9604 (a synthetic peptide fragment of human growth hormone) alone and in combination with hyaluronic acid (HA) in a collagenase-induced knee osteoarthritis (OA) rabbit model. Thirty-two mature New Zealand white rabbits had OA induced in both knees via collagenase injection, then were divided into four groups receiving weekly intra-articular injections of saline, HA alone, AOD9604 alone, or AOD9604 combined with HA. At eight weeks, outcomes were assessed via gross morphology, histopathology of cartilage, and lameness scoring. The study found that all treatment groups showed significantly less cartilage degeneration than the saline control group. The combination of AOD9604 and HA produced significantly lower cartilage damage scores and shorter lameness periods compared to either treatment alone. While these findings suggest a potential chondroprotective and synergistic effect, the study is limited by its animal-only design, relatively small group sizes, and the use of a chemically induced OA model that may not fully replicate human OA pathology. No human data were collected, so translation of findings to clinical practice remains uncertain.
Annals of clinical and laboratory science · Jan 2015Source ↗ Review
This review paper surveys the current landscape of analytical methods used in sports anti-doping laboratories to detect peptide-based drugs, drug candidates, and their analogs in biological specimens such as blood, serum, and urine. The authors describe the broad range of peptidic compounds subject to anti-doping scrutiny, spanning low-molecular-mass peptides (e.g., growth hormone-releasing peptides, ARA-290, TB-500, AOD-9604, CJC-1295, desmopressin) to intermediate-mass proteins (e.g., insulins, IGF-1, growth hormone, erythropoietin) and higher-molecular-mass biologics (e.g., stamulumab). The review outlines detection approaches including chromatographic-mass spectrometric, electrophoretic, immunological, and combined methodologies, emphasizing the challenge of proving exogenous origin at very low concentrations in limited sample volumes. A central finding is that a meaningful gap remains between what is technically achievable in detection and what is routinely practiced in day-to-day analytical workflows. Limitations of this paper include its nature as a narrative review rather than an original experimental study, meaning it synthesizes existing literature without generating new empirical data. It does not evaluate clinical outcomes or therapeutic efficacy of any compound discussed.
Expert review of proteomics · Nov 2014DOI ↗ In vitro
This study focused on developing analytical methods to detect AOD9604 — a synthetic peptide derived from the C-terminal fragment (residues 177–191) of human growth hormone with an added N-terminal tyrosine — in biological samples for anti-doping purposes. AOD9604 is reported to mimic the lipolytic effects of growth hormone without diabetogenic side effects, making it a candidate performance-enhancing drug banned by WADA. Researchers validated a solid-phase extraction method for detecting AOD9604 in urine, achieving a limit of detection of 50 pg/mL with acceptable linearity, precision (below 20%), specificity, and recovery (62%). The study also characterized in vitro metabolism by incubating AOD9604 in serum and urine, identifying six potential metabolites. Quantification in serum revealed one notably stable metabolite — a peptide fragment consisting of the amino acid sequence CRSVEGSCG — that persisted longer than both the parent compound and other metabolites. The authors suggest that screening for both AOD9604 and this stable metabolite could extend the detection window in doping controls. Limitations include the in vitro nature of the metabolic data, meaning real-world metabolic behavior in human subjects in vivo remains uncharacterized.
Drug testing and analysis · Sep 2014DOI ↗ Review
This review summarizes five years of published literature on the analytical detection of emerging and non-approved performance-enhancing substances in the context of sports anti-doping controls. The authors examine a broad range of compounds classified as doping agents by the World Anti-Doping Agency (WADA), spanning both peptidic substances—such as modified insulin-like growth factor-1 (IGF-1), TB-500 (thymosin beta-4 fragment), peginesatide/hematide, growth hormone releasing peptides, and AOD-9604—and non-peptidic substances, including selective androgen receptor modulators (SARMs), hypoxia-inducible factor (HIF) stabilizers, siRNA, S-107, and aladorian (ARM036). Inorganic substances such as cobalt are also discussed. The review focuses specifically on the analytical challenges posed by these compounds, including their physicochemical properties, low concentrations in biological matrices (blood and urine), metabolic transformation, and suitability for chromatographic–mass spectrometric or alternative detection methods. The study does not present original experimental data or human clinical outcomes, but rather synthesizes existing literature to guide development of detection strategies. A key limitation is that, as a review, it does not independently validate any analytical method and reflects the state of the field only up to its publication date.
Journal of pharmaceutical and biomedical analysis · May 2014DOI ↗ Animal only
This animal study investigated how human growth hormone (hGH) and a synthetic lipolytic fragment derived from its C-terminus, AOD9604, affect fat metabolism and body weight in obese and genetically modified mice. Obese mice received 14 days of chronic intraperitoneal administration of either compound. Both hGH and AOD9604 reduced body weight and body fat in obese mice, and these effects were associated with increased expression of beta-3 adrenergic receptor (β3-AR) RNA — a key receptor involved in fat breakdown — bringing levels in obese mice closer to those seen in lean mice. To test whether β3-AR was essential to these effects, the researchers used β3-AR knock-out mice; in these animals, chronic treatment with either compound failed to produce the body weight reduction or increased lipolysis seen in normal mice. However, in an acute experiment, AOD9604 still increased energy expenditure and fat oxidation in knock-out mice, suggesting additional mechanisms exist. The authors concluded that while neither compound acts directly through β3-AR, both upregulate its expression, which may amplify lipolytic sensitivity over time. Key limitations include the exclusively animal-based design and the use of intraperitoneal administration, limiting direct translation to humans.
Endocrinology · Dec 2001DOI ↗