This is a working overview of Investigational drug, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-02-19 and is reviewed periodically as new material appears.
Legal status varies by country. In some places, cardarine is controlled under medicines or psychoactive substances laws; in others, it may be sold with minimal oversight as a research chemical. Customs agencies have intercepted shipments, and several national health agencies have issued warnings about products marketed for bodybuilding or performance enhancement. The lack of a standardized pharmaceutical supply means identity, purity, and contamination levels can differ widely between samples. These factors make cardarine a regulatory and public health concern rather than a conventional prescription drug.
Cardarine is a common name for GW501516, a synthetic compound first described in the 1990s as a selective agonist of the peroxisome proliferator-activated receptor delta. It was studied in preclinical models for metabolic and cardiovascular conditions, but it has not been approved as a medicine in the United States, Europe, or other major jurisdictions. Retail products labeled as cardarine are generally research chemicals or supplements, not pharmaceutical formulations. Because human safety and efficacy data remain limited, regulatory agencies treat it as an unapproved substance rather than a therapeutic product.
Sporting authorities added GW501516 to prohibited lists after it appeared in athlete samples and online markets. The World Anti-Doping Agency classifies it as a hormone and metabolic modulator, and its use can lead to an anti-doping rule violation. Some early laboratory work suggested effects on fatty acid oxidation and endurance-related metabolism in animals, but those findings do not establish safe or effective use in people. Reports of adverse events in humans are scarce and often anecdotal, which complicates risk assessment.
PPARδ is a nuclear receptor that influences transcription of genes involved in fatty acid oxidation, lipid transport, and energy homeostasis. GW501516 binds and activates this receptor with high selectivity relative to PPARα and PPARγ in laboratory assays. Activation alters expression of target genes in skeletal muscle, liver, and adipose tissue in animal models. The exact clinical consequences of these changes in humans remain incompletely characterized, and observed effects in animals do not establish therapeutic benefit or safety.
Published studies have examined GW501516 in animal models of obesity, insulin resistance, and exercise endurance. Early human trials reportedly ended, and development was discontinued after preclinical findings raised concerns about cancer in some rodent studies. Regulatory agencies have not approved cardarine for any medical use. Its availability through non-pharmaceutical channels raises questions about identity, purity, and legal status that are separate from its laboratory pharmacology. Those questions are often addressed through analytical testing rather than assumptions about product labels.
Cardarine is a common name for GW501516, also GW-1516, a synthetic compound developed as a peroxisome proliferator-activated receptor delta (PPARδ) agonist. It belongs to a class of agents that modulate gene transcription related to lipid and energy metabolism. The compound was studied in preclinical and early clinical research for metabolic and cardiovascular conditions, but it did not progress to approved therapeutic use. Its name appears in fitness and sports contexts despite not being approved as a drug.
| Property | Value | Notes |
|---|---|---|
| IUPAC name | {4-[({4-methyl-2-[4-(trifluoromethyl)phenyl]-1,3-thiazol-5-yl}methyl)sulfanyl]phenoxy}acetic acid | Systematic name for GW501516 |
| CAS Registry Number | 317318-70-0 | Unique identifier for the parent compound |
| Molecular formula | C21H18F3NO3S2 | Includes carbon, hydrogen, fluorine, nitrogen, oxygen, and sulfur |
| Molecular weight | 453.5 g/mol | Approximate value for the neutral form |
| Appearance | White to off-white powder | Typical description for purified laboratory material |
Handling and quality assessment of cardarine reference material follow general laboratory practices for poorly characterized compounds. It typically appears as a white to off-white powder and is sparingly soluble in water but soluble in organic solvents such as dimethyl sulfoxide and ethanol. Storage recommendations usually specify a cool, dry, dark place, with long-term storage at low temperature and desiccation. Purity may be checked by high-performance liquid chromatography with ultraviolet detection, while identity is confirmed by mass spectrometry and nuclear magnetic resonance. No pharmacopeial monograph exists, so reported purity and stability depend on the supplier’s methods.
GW501516 acts as a selective agonist at PPARδ, a nuclear receptor that regulates transcription of genes involved in lipid handling and energy metabolism. Activation of PPARδ in preclinical models increases fatty acid oxidation, mitochondrial biogenesis, and exercise endurance in rodents. These effects have made the compound a subject of metabolic research and also a target for sport anti-doping rules. In humans, however, controlled studies are limited, and whether similar endurance or metabolic changes occur at tolerated exposures remains an open question. The receptor’s broad tissue distribution also means downstream effects may vary by organ and condition.
Anti-doping laboratories detect GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be used in some programs. Detection depends on factors such as dose, timing, metabolism, and the sensitivity of the assay. Published methods describe limits of detection in the low nanogram per milliliter range for related compounds. Exact detection windows are not fixed for all situations and remain an area of ongoing study.
Products sold as cardarine have been found to contain incorrect compounds, variable amounts, or no active ingredient at all. Independent testing is required to verify identity and purity. Common analytical approaches include high-performance liquid chromatography, mass spectrometry, and nuclear magnetic resonance for structural confirmation. These methods can distinguish GW501516 from related PPAR agonists and from unrelated steroids. For regulators and researchers, such verification is central to interpreting both biological results and adverse event reports.
Laboratory handling focuses on identity, purity, and stability. Reference standards are typically stored cold and dry, protected from light, because solutions can degrade over time. Analytical checks may use high-performance liquid chromatography with ultraviolet detection or mass spectrometry. Impurities and related substances can be separated chromatographically and compared with a known standard. Because cardarine is not an approved drug, compendial monographs are absent, and laboratories often rely on in-house methods. Reported purity varies among unregulated products and should not be assumed from a label.
GW501516 binds and activates PPARδ, a nuclear receptor that influences transcription of genes involved in fatty acid oxidation and energy use. Activation shifts some metabolic pathways in preclinical models, which is why the compound has been studied for lipid disorders and exercise-related endpoints. The exact downstream effects in humans are incompletely mapped. PPARδ is expressed in many tissues, including skeletal muscle, liver, and adipose tissue, so broad activation may have varied consequences. Researchers continue to examine how selective or partial activation might alter the balance between benefits and risks.
GW501516 acts on PPARδ, a nuclear receptor that helps regulate fatty acid oxidation and energy homeostasis. In animal studies, activation of this receptor was associated with increased endurance and changes in lipid metabolism. Human trials examined effects on blood lipids and other metabolic markers, but the compound did not advance to approval. Rodent studies later reported tumors in multiple tissues at doses used in those experiments. Whether those findings translate to human risk remains uncertain, and the clinical relevance of the animal data is still debated.
Regulatory bodies treat GW501516 as a prohibited substance in competitive sport. The World Anti-Doping Agency added it to the prohibited list, and it falls under classes covering metabolic modulators and hormone-related agents. It is not approved by drug regulators for human use, and it is not a lawful dietary supplement. Products sold under the cardarine name may contain unlisted ingredients or different compounds. Because no approved product exists, quality and identity are not guaranteed by pharmaceutical manufacturing standards.
== Use in dermatology == Mequinol is a common active ingredient in topical drugs used for skin depigmentation. As a topical drug mequinol is often mixed with tretinoin, a topical retinoid. A common formulation for this drug is an ethanolic solution of 2% mequinol and 0.01% tretinoin by mass. Dermatologists commonly prescribe the drug to treat liver spots. Lower dosages of mequinol have been used in conjunction with a Q-switched laser to depigment skin in patients with disseminated idiopathic vitiligo.
==== Alzheimer's disease ==== A case-control study in a Japanese population showed that deficiency of ALDH2 activity influences the risk for late-onset Alzheimer's disease. The ALDH2 knockout mice display age-related memory deficits in various tasks, as well as endothelial dysfunction, brain atrophy, and other Alzheimer's disease-associated pathologies, including marked increases in lipid peroxidation products, amyloid-beta, p-tau and activated caspases. These behavioral and biochemical Alzheimer's disease-like deficits were efficiently ameliorated when these mice were treated with isotope-reinforced lipids (deuterated polyunsaturated fatty acids).
Gene targeting techniques, which creates double-stranded breaks and takes advantage on the cells natural homologous recombination repair systems, have been developed to target insertion to exact locations. Genome editing uses artificially engineered nucleases that create breaks at specific points. There are four families of engineered nucleases: meganucleases, zinc finger nucleases, transcription activator-like effector nucleases (TALENs), and the Cas9-guideRNA system (adapted from CRISPR). TALEN and CRISPR are the two most commonly used and each has its own advantages. TALENs have greater target specificity, while CRISPR is easier to design and more efficient.
In addition, the serotonin 5-HT1B receptor has been found to be required for psilocybin's persisting antidepressant- and anxiolytic-like effects as well as acute hypolocomotion in animals. In humans, ketanserin blocked psilocybin's hallucinogenic effects but not all of its cognitive and behavioral effects. Serotonin 5-HT2C receptor activation and downstream inhibition of the mesolimbic dopamine pathway may be involved in the limited addictive potential of serotonergic psychedelics like psilocybin. The drug shows pronounced biased agonism at the serotonin 5-HT2C receptor. In addition to its psychedelic effects, psilocin has been found to produce psychoplastogenic effects in animals, including dendritogenesis, spinogenesis, and synaptogenesis. It has been found to promote neuroplasticity in the brain in a rapid, robust, and sustained manner with a single dose. These effects appear to be mediated by intracellular serotonin 5-HT2A receptor activation. The psychoplastogenic effects of psilocybin and other serotonergic psychedelics may be involved in their potential therapeutic benefits in the treatment of psychiatric disorders such as depression. They may also be involved in the effects of microdosing. Psilocin was also reported to act as a highly potent positive allosteric modulator of the tropomyosin receptor kinase B (TrkB), one of the receptors of brain-derived neurotrophic factor (BDNF), but subsequent studies failed to reproduce these findings and instead found no interaction of psilocin with TrkB.
Sources: en.wikipedia.org
=== Noise reduction === Noise reduction can be accomplished either in computer hardware or software. Examples of hardware noise reduction are the use of shielded cable, analog filtering, and signal modulation. Examples of software noise reduction are digital filtering, ensemble average, boxcar average, and correlation methods.
Studies show this method is at least as good at preventing flystrike as mulesing and carries few long-term consequences for the lamb's later growth. Steinfort and others invested in the process have claimed it is less painful and distressing than mulesing to the animals on which it is practiced. They argue that affected nerve endings are immediately numbed and that sensation does not return during healing when a scab forms and is eventually sloughed in 6 to 8 weeks. A 2018 study found behavioral markers indicating pain and distress in lambs who had been steined without analgesic treatment compared to those who had been given analgesics. In 2020 a University of Melbourne researcher named Ellen Jongman was commissioned to study the issue by the company Steinfort formed to commercialize his technique, SteinfortAgVet. On December 22, 2020, she released preliminary results from her study on the relative pain of mulesing and steining. Jongman found that mulesing and steining were equally painful on the day of the procedure but that steined lambs appeared to be in less pain than mulesed lambs on subsequent days. Her study tracked and interpreted a series of lamb behaviors like the speed at which it returned to its mother after undergoing either mulesing or steining. She called for further research using physiological data such as heart rate and blood sampling in addition to behavioral observations. Jongman's final report was released on January 25, 2021. In March 2021 AWN cut ties with Steinfort and divested from this application of freeze branding.
Acetyl-CoA can be metabolized through the TCA cycle in any cell, but it can also undergo ketogenesis in the mitochondria of liver cells. When glucose availability is low, oxaloacetate is diverted away from the TCA cycle and is instead used to produce glucose via gluconeogenesis. This utilization of oxaloacetate in gluconeogenesis can make it unavailable to condense with acetyl-CoA, preventing entrance into the TCA cycle. In this scenario, energy can be harvested from acetyl-CoA through ketone production. In ketogenesis, two acetyl-CoA molecules condense to form acetoacetyl-CoA via thiolase. Acetoacetyl-CoA briefly combines with another acetyl-CoA via HMG-CoA synthase to form hydroxy-β-methylglutaryl-CoA. Hydroxy-β-methylglutaryl-CoA form the ketone body acetoacetate via HMG-CoA lyase. Acetoacetate can then reversibly convert to another ketone body—D-β-hydroxybutyrate—via D-β-hydroxybutyrate dehydrogenase. Alternatively, acetoacetate can spontaneously degrade to a third ketone body (acetone) and carbon dioxide, which generates much greater concentrations of acetoacetate and D-β-hydroxybutyrate. The resulting ketone bodies cannot be used for energy by the liver so are exported from the liver to supply energy to the brain and peripheral tissues. In addition to fatty acids, deaminated ketogenic amino acids can also be converted into intermediates in the citric acid cycle and produce ketone bodies.
Mitogen-activated protein kinase 3 (MAPK3) is also known as extracellular signal-regulated kinase 1 (ERK1). Transgenic gene knockout mice lacking MAPK3 are viable and it is thought that MAPK1 can fulfill some MAPK3 functions in most cells. The main exception is in T cells. Mice lacking MAPK3 have reduced T cell development past the CD4+ and CD8+ stage.
== Enhanced chemiluminescence == Enhanced chemiluminescence (ECL) is a common technique for a variety of detection assays in biology. A horseradish peroxidase enzyme (HRP) is tethered to an antibody that specifically recognizes the molecule of interest. This enzyme complex then catalyzes the conversion of the enhanced chemiluminescent substrate into a sensitized reagent in the vicinity of the molecule of interest, which on further oxidation by hydrogen peroxide, produces a triplet (excited) carbonyl, which emits light when it decays to the singlet carbonyl. Enhanced chemiluminescence allows detection of minute quantities of a biomolecule. Proteins can be detected down to femtomole quantities, well below the detection limit for most assay systems.
Sources: en.wikipedia.org
For services to Seriously and Terminally Ill Children and their Families. Kevin Shakesheff. Co-Founder, High Tide Foundation and President, Institute of Chartered Shipbrokers and Educational Fund. For services to Young People in Business and to the Maritime Industry. Ian James Donald Sharp. Lately Captain, 6th Wolverhampton Boys' Brigade. For services to Young People in Wolverhampton. Yassamin Sheel. National Lead, United Teaching, Greater Manchester. For services to Children. Karen Eileen Shepperson. Director of People and Operations, Ofsted. For services to Education. Savraj Singh Shetra. Field Intelligence Officer, Home Office. For Public Service. Dr. Hamsaraj Gundal Mahabala Shetty. Consultant Physician, University Hospital of Wales. For services to Stroke Services in Wales. David Alan Short, JP. Lately Group Technology Director, BAE Systems. For services to Military Capability. David Norman Short. For services to Pastoral Care and to the community in Buckinghamshire. John Stanley William Simpson. For services to Agriculture and to the community in Lewes, East Sussex. Margaret Ann Simpson. For services to the community in Oxfordshire. Roselind Pamela Sinclair. Lecturer in Design Education, Goldsmiths, University of London. For services to the Arts. Nirmal Singh. Chaplain, North West Prisons HM Prison and Probation Service. For services to Community Development and Interfaith Integration. Catherine Elizabeth Skidmore. Head of Aviation Resilience, Department for Transport. For services to Major Event Responses. Christopher Jon Smith.
== International Organization for Standardization (ISO) == CLSI participates in the development of international standards as the Secretariat of ISO Technical Committee (TC) 212, clinical laboratory testing and in vitro diagnostic test systems. This responsibility was delegated to CLSI by the American National Standards Institute (ANSI), an ISO member body. CLSI also serves as the administrator for the US Technical Advisory Committee (TAG) for ISO/TC 212.
=== Prostate cancer === CPA is used as an antiandrogen monotherapy and means of androgen deprivation therapy in the palliative treatment of prostate cancer in men. It is used at very high doses by mouth or by intramuscular injection to treat this disease. Antiandrogens do not cure prostate cancer, but can significantly extend life in men with the disease. CPA has similar effectiveness to GnRH modulators and surgical castration, high-dose estrogen therapy (e.g., with diethylstilbestrol), and high-dose nonsteroidal antiandrogen monotherapy (e.g., with bicalutamide), but has significantly inferior effectiveness to combined androgen blockade with a GnRH modulator and a nonsteroidal antiandrogen (e.g., with bicalutamide or enzalutamide). In addition, the combination of CPA with a GnRH modulator or surgical castration has not been found to improve outcomes relative to a GnRH modulator or surgical castration alone, in contrast to nonsteroidal antiandrogens. Due to its inferior effectiveness, tolerability, and safety, CPA is rarely used in the treatment of prostate cancer today, having largely been superseded by GnRH modulators and nonsteroidal antiandrogens. CPA is the only steroidal antiandrogen that continues to be used in the treatment of prostate cancer. Dose-ranging studies of CPA for prostate cancer were not performed, and the optimal dosage of CPA for the treatment of the condition has not been established. A dosage range of oral CPA of 100 to 300 mg/day is used in the treatment of prostate cancer, but generally 150 to 200 mg/day oral CPA is used.
=== Motivational disorders === Selegiline has been found to produce pro-motivational effects and to reverse motivational deficits in rodents. In case reports and small clinical studies, selegiline has been reported to improve disorders of diminished motivation like apathy and abulia due to conditions such as traumatic brain injury. In accordance with the preceding findings, selegiline, along with other dopaminergic and activating agents, may be useful in the treatment of disorders of diminished motivation, including apathy, abulia, and akinetic mutism.
Sources: en.wikipedia.org
No. Major drug regulators have not approved GW501516 for treating any medical condition. Products sold as cardarine are typically unapproved research chemicals or supplements, so their contents and safety are not assured.
It is prohibited by the World Anti-Doping Agency as a hormone and metabolic modulator. Athletes who test positive for GW501516 can face sanctions, including suspensions and loss of results.
Cardarine is a common or trade-style name, while GW501516 is the research code for the same chemical entity. Some sources also use Endurobol or GSK-516. The names refer to the same compound, not distinct drugs.
Cardarine is commonly known as GW501516 or GW-1516. These names refer to the same synthetic compound. It is not a brand-name approved medicine.