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Identity And Regulatory Status — Worked Examples

By Editorial Desk · published 2026-03-04 · last reviewed 2026-04-04 · Faq

PPARδ agonist raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.

Reviewed 2026-04-04. Anything still debated is marked as such rather than presented as settled.

Identity and Regulatory Status

Regulatory treatment varies, but cardarine is not approved as a medicine. Sports authorities list GW501516 as a prohibited substance, and it is banned at all times under the World Anti-Doping Agency code. Many countries restrict sales for human consumption, while online vendors market it as a research chemical. Such products may lack purity data, and their actual contents can differ from the label. Purchasing or possessing cardarine may carry legal consequences depending on jurisdiction. The compound is not a dietary supplement ingredient in regulated markets.

Clinical development stopped after rodent studies showed tumors at multiple sites. Whether those findings predict human cancer risk remains an open question, but they led sponsors to discontinue programs. Human safety data are limited to small, short-term studies that were not designed to assess cancer risk. Reported effects in those studies included changes in blood lipids, but the evidence is insufficient for medical use. Long-term consequences of nonmedical use are not well characterized. Questions about dose, duration, and individual susceptibility remain unresolved.

Cardarine is a common name for GW501516, an investigational compound developed in the 1990s for metabolic conditions. It acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in lipid and energy metabolism. The compound is frequently mislabeled as a selective androgen receptor modulator, or SARM, but its molecular target is different. GW501516 reached early clinical testing before development was discontinued. It has no approved therapeutic use in any country. The name cardarine is not a formal international nonproprietary name.

Mechanism and Detection

Anti-doping laboratories identify GW501516 and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is the usual matrix, and detection can occur after the parent compound has cleared from blood. The exact detection window depends on dose, formulation, individual metabolism, and assay sensitivity. Because the compound is prohibited at all times, athletes are subject to testing in and out of competition. Analytical methods continue to improve as new metabolites and designer analogs are characterized.

GW501516 acts as a ligand for PPAR delta, a nuclear receptor that regulates transcription of genes involved in fatty acid oxidation and energy use. Activation of this receptor in skeletal muscle shifts metabolism toward fat burning in animal models. The compound does not burn fat directly; it changes gene expression over hours to days. Researchers study it to understand metabolic flexibility and exercise adaptation. Effects observed in rodents are not automatically expected in humans.

Cardarine at a glance

PropertyValueNotes
Common synonymsGW501516; GW-1516; endurobolGW501516 is the research code
Drug classPPARδ agonistNot a selective androgen receptor modulator
Molecular formulaC21H18F3NO3S2Established chemical formula
Molar mass453.5 g/molCalculated from the formula
Regulatory statusProhibited in sport; not approved as medicineStatus varies by country

Identity and Pharmacological Mechanism

The compound is typically described as a laboratory compound rather than a therapeutic product. Published reports have explored its role in lipid disorders, insulin sensitivity, and exercise metabolism, yet no major drug regulator has approved it for medical use. Commercial samples sold under the cardarine name may vary in purity and identity. Analytical confirmation is therefore necessary when the material is discussed in scientific or regulatory contexts. Its classification as a prohibited substance in sport further shapes how it is studied and reported.

Cardarine is a common name for GW501516, a synthetic compound studied for its effects on lipid and glucose metabolism. It functions as an agonist at peroxisome proliferator-activated receptor delta, or PPARδ, a nuclear receptor that influences gene expression. The molecule is not a steroid, nor is it a selective androgen receptor modulator. It is also known in research and sports literature as GW-501516 and endurobol. Early laboratory work examined its metabolic activity in cell cultures and animal models.

Related pages on this site

Cardarine as Investigational PPARδ Agonist

Safety discussions about cardarine frequently cite rodent carcinogenicity findings reported in the 2000s. In those studies, treated animals developed tumors at multiple sites, leading sponsors to discontinue clinical development. The relevance of these findings to humans has not been resolved, but they are a major reason the compound is not approved. Current literature emphasizes uncertainty about long-term effects and the risks of unregulated use. Regulators and health agencies have not established a safe human exposure level.

Cardarine is a synthetic compound also known as GW501516, GW-501516, and sometimes endurobol. It was developed as a selective agonist of peroxisome proliferator-activated receptor delta, a nuclear receptor involved in fatty acid oxidation and energy metabolism. The compound was studied in preclinical models for metabolic and cardiovascular conditions, but it did not become a marketed human medicine. In regulatory and anti-doping contexts, it is treated as a prohibited substance rather than a licensed medicine.

The pharmacological interest in cardarine centers on PPARδ activation and its downstream effects on lipid handling and mitochondrial function. In animal studies, PPARδ agonists have been associated with changes in exercise endurance and fatty acid utilization, though results vary by model and protocol. Human data remain sparse, and the absence of large controlled trials limits conclusions about efficacy. Researchers often describe the compound as a tool for probing PPARδ biology rather than a proven therapeutic agent.

Detection, Regulation, and Quality Context

Because cardarine is not an approved medicine, no pharmacopeial monograph defines its identity, purity, or storage requirements. Laboratories typically rely on in-house methods and reference standards when testing materials labeled as GW501516. Certificates of analysis may report purity and identity for a specific batch, but their scope varies and they do not guarantee safety or legal status. Independent verification can include high-performance liquid chromatography, mass spectrometry, nuclear magnetic resonance, and elemental analysis. The distinction between research chemical labeling and human use is significant because quality standards and oversight differ.

Cardarine can be detected in biological samples and product materials using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method separates compounds by chromatography and identifies them by mass-to-charge transitions, allowing low-level detection in urine or blood. Sample preparation often involves enzymatic hydrolysis, solid-phase extraction, or protein precipitation. Certified reference materials and isotope-labeled internal standards improve quantification. Detection windows depend on metabolism, matrix, and assay sensitivity, so no single universal window applies.

Regulatory treatment of cardarine differs by context and jurisdiction. In competitive sport, the World Anti-Doping Agency lists PPARδ agonists, including GW501516, as prohibited at all times. Outside sport, it lacks approval as a prescription medicine in major drug markets, and products sold for human consumption may be treated as unapproved drugs. Some countries also restrict importation or sale through general consumer protection and medicines laws. These classifications affect availability, testing, and legal risk without establishing therapeutic value.

Background and Research Context

In laboratory settings, cardarine is studied as a tool compound for probing PPARδ biology. Published experiments often use cell cultures, rodent models, or isolated tissues. Some investigations focus on metabolic effects, while others assess potential risks such as carcinogenicity observed in long-term animal studies. Because human trials are sparse, most knowledge comes from preclinical work and adverse event reports. Scientific literature frequently notes the gap between animal findings and human outcomes. The compound is not a dietary supplement and is not intended for human consumption.

Cardarine is a common name for GW501516, a synthetic compound developed in the 1990s through research collaborations involving GlaxoSmithKline. It belongs to a class of molecules known as peroxisome proliferator-activated receptor delta agonists. Early studies explored its effects on lipid metabolism and energy expenditure in animal models. The compound was never approved as a human medicine, and clinical development was discontinued. In the years since, it has appeared in fitness and bodybuilding communities as a performance-enhancing substance. Regulatory agencies classify it as an unapproved drug.

PPARδ is a nuclear receptor that regulates gene expression related to fatty acid oxidation, glucose homeostasis, and mitochondrial function. GW501516 binds to this receptor with high affinity and activates downstream signaling in skeletal muscle and other tissues. Animal studies reported increased endurance and altered fuel preference, but human data remain limited and inconsistent. The precise relationship between receptor activation and observed physiological changes is still an area of active investigation. Researchers have also examined whether the compound affects inflammation or cell proliferation. No approved therapeutic indication exists for cardarine.

Background from the literature

=== Hippurate === The Hippurate diagnostic test is used to differentiate between Gardnerella vaginalis, Campylobacter jejuni, Listeria monocytogenes and group B streptococci using the chemical Hippurate. The Hippurate hydrolysis pathway, capable by organisms with the necessary enzymes, produces glycine as a byproduct. Using the indicator ninhydrin, which changes color in the presence of glycine, will display either a colorless product, a negative result, of a dark blue color, a positive result.

In the midst of this political climate, the two major events planned for 1992 ─ the 1992 Summer Olympics and the 1992 Seville Expo ─ were held, which provided "the opportunity to present Spain in the Columbus Quincentenary as a modern country, definitely away from the romantic stereotype (of charanga, tambourine, bandits and toreros)". This new image of Spain was accompanied by the strengthening of its international role, such as the holding in Madrid of the Middle East Peace Conference and the active participation of Felipe González in the approval of the Maastricht Treaty which transformed the European Community into the new European Union. Likewise, the Spanish government sent three Navy units to support US-led allied military operations during the First Gulf War of 1990–1991. However, the two great events of 1992 and the resounding success of the anti-terrorist policy that led to the arrest of the three top leaders of ETA in the French town of Bidart, could not hide the fact that a strong economic recession had begun, which resulted in a brutal increase in unemployment that would reach an unprecedented figure of 3.5 million unemployed, representing 24% of the working population. Also that same year, a general strike called by UGT and Comisiones Obreras occurred in protest against the government's "decretazo" cutting unemployment benefits. The deteriorating economic situation and social climate, together with internal divisions within the PSOE, led Felipe González to bring forward the general elections to June 1993.

The definitions of the pressure ulcer stages are revised periodically by the National Pressure Injury Advisory Panel (NPIAP) in the United States and the European Pressure Ulcer Advisory Panel (EPUAP) in Europe. Different classification systems are used around the world, depending upon the health system, the health discipline and the purpose for the classifying (e.g. health care versus, prevalence studies versus funding. Briefly, they are as follows:

== Early life, education and career == Moroder studied chemistry at the University of Padova, where he graduated 1965 in chemistry with the doctoral thesis on synthesis of S-peptide of ribonuclease A in the laboratory of Ernesto Scoffone at the Institute of Organic Chemistry. In 1968 he joined Klaus H. Hofmann's Group at the University of Pittsburgh to work on chemical synthesis of the peptidic adrenocorticotropic hormone and its derivatives. Moroder habilitated in 1971 at the University of Padova in Chemistry of Natural Products. 1975 he became a senior research fellow in the Department of Peptide Chemistry at the Max Planck Institute for Biochemistry (MPIB) in Martinsried headed by Erich Wünsch. Between 1991 and 2008 he was the head of the Laboratory of Bioorganic chemistry at the MPIB. Since 1994 he was an adjunct professor at the Technical University of Munich.

A Study published by Altus Group indicates that 383 pubs closed in England during the first six months of 2023, including 46 in London. 9 October – Medway Council in Kent cancels its 2023 Christmas lights due to what it describes as a "challenging financial situation". 11 October – South Yorkshire Police says it is making "ongoing" inquiries after video footage emerged of a man climbing onto the roof of Sheffield Town Hall to replace an Israeli flag with a Palestinian one. An Independent Monitoring Board report into Wandsworth Prison has concluded that the prison is "unsafe and inhumane"; the report was prepared before the escape of Daniel Khalife in September. 12 October – Following reports that some student societies have been distributing leaflets in support of Hamas, education ministers Gillian Keegan and Robert Halfon have written to university vice chancellors in England urging them to "act swiftly and decisively against any threats" to students' safety and welfare. The number of people waiting for planned NHS treatment in England rises to 7.75 million. 13 October – Three Jewish schools in north London have closed for the day amid safety concerns for their students because of the ongoing conflict between Israel and Hamas. Police have detailed a 22-year-old woman on suspicion of supporting Hamas, which is a prescribed terrorist organisation in the UK, following a speech given at a protest in Brighton on 8 October.

Sources: en.wikipedia.org

Reference notes

=== Marriage === He married Jane Winifred "Jennie" Stirling (1881–1966), the third daughter of his former professor, Sir Edward Stirling, at Mount Lofty, South Australia on 1 July 1910. They had three children: Judith Stirling Robertson (1917–2012), later, Mrs. Herbert Charles Vaughan Woollard, the physicist and amateur radio operator, David Stirling Robertson, B.Sc., M.Sc., Ph.D., D.Sc. (1920–1999), and the medical practitioner, Thorburn Stirling Brailsford Robertson, M.B. B.S. (1925–1966), known as "Stirling".

Cantons of Switzerland Composition of the German state parliaments Elections in Germany German Bundesländer €2 coins Landespolizei – German state police List of administrative divisions by country List of cities and towns in Germany List of German states by area List of German states by exports List of German states by fertility rate List of German states by GRP List of German states by household income List of German states by Human Development Index List of German states by life expectancy List of German states by population List of German states by population density List of German states by poverty rate List of German states by unemployment rate List of states in the Holy Roman Empire – the German states prior to 1815 States of Austria

Carl Linnaeus originally classified bananas into two species based only on their uses as food: Musa paradisiaca for plantains and Musa sapientum for dessert bananas. Both are now known to be hybrids between the species Musa acuminata (A genome) and Musa balbisiana (B genome). The earlier published name, Musa × paradisiaca, is now used as the scientific name for all such hybrids. Most modern plantains are sterile triploids belonging to the AAB Group, sometimes known as the "Plantain group". Other economically important cooking banana groups include the East African Highland bananas (Mutika/Lujugira subgroup) of the AAA Group and the Pacific plantains (including the Popoulo, Maoli, and Iholena subgroups), also of the AAB Group.

=== Fire-retardant additives === Melamine and its salts are used as fire-retardant additives in paints, plastics, and paper. A melamine fiber, Basofil, has low thermal conductivity, excellent flame resistance and is self-extinguishing; this makes it useful for flame-resistant protective clothing, either alone or as a blend with other fibres.

=== Antimicrobial surfaces === Antimicrobial surfaces are designed to either inhibit the ability of microorganisms to grow or damaging them by chemical (copper toxicity) or physical processes (micro/nano-pillars to rupture cell walls). These surfaces are especially important for the healthcare industry. Designing effective antimicrobial surfaces demands an in-depth understanding of the initial microbe-surface adhesion mechanisms. Molecular dynamics simulation and time-lapse imaging are typically used to investigate these mechanisms.

Sources: en.wikipedia.org

Notes from published material

At the February 1945 Yalta Conference, the Allies attempted to define the framework for a postwar settlement in Europe. The Allies could not reach firm agreements on the crucial questions: the occupation of Germany, postwar reparations from Germany, and the fate of Poland. No final consensus was reached on Germany, other than to agree to a Soviet request for reparations totaling $10 billion "as a basis for negotiations". Debates over the composition of Poland's postwar government were also acrimonious. The Yalta Conference ended with "a declaration on liberated Europe pledging respect for democratic forms and providing a diplomatic mechanism for constituting a generally acceptable Polish government". After Roosevelt's death on April 12, Harry S. Truman succeeded him as US president. Truman was unaware of Roosevelt's plans for post-war engagement with the Soviet Union, and more generally uninformed about foreign policy and military matters. The new president, therefore, was initially reliant on a set of advisers (including Ambassador to the Soviet Union Averell Harriman and Secretary of the Navy James Forrestal). This group tended to take a harder line towards Moscow than Roosevelt had done. Truman lacked the foreign policy confidence that pushed Roosevelt's initiatives with the Soviet Union. Eager to prove himself, Truman depended on his advisors, with Harriman using this lack of confidence to push his argument that Roosevelt's position on Stalin was based on fear, therefore Truman needed to prove the grit of the US. US-Soviet relations became decidedly colder.

Angiotensin II also acts on the smooth muscle in the walls of the arterioles causing these small diameter vessels to constrict, thereby restricting the outflow of blood from the arterial tree, causing the arterial blood pressure to rise. This, therefore, reinforces the measures described above (under the heading of "Arterial blood pressure"), which defend the arterial blood pressure against changes, especially hypotension. The angiotensin II-stimulated aldosterone released from the zona glomerulosa of the adrenal glands has an effect on particularly the epithelial cells of the distal convoluted tubules and collecting ducts of the kidneys. Here it causes the reabsorption of sodium ions from the renal tubular fluid, in exchange for potassium ions which are secreted from the blood plasma into the tubular fluid to exit the body via the urine. The reabsorption of sodium ions from the renal tubular fluid halts further sodium ion losses from the body, and therefore preventing the worsening of hyponatremia. The hyponatremia can only be corrected by the consumption of salt in the diet. However, it is not certain whether a "salt hunger" can be initiated by hyponatremia, or by what mechanism this might come about. When the plasma sodium ion concentration is higher than normal (hypernatremia), the release of renin from the juxtaglomerular apparatus is halted, ceasing the production of angiotensin II, and its consequent aldosterone-release into the blood. The kidneys respond by excreting sodium ions into the urine, thereby normalizing the plasma sodium ion concentration.

For spherical polymer nanoparticles, glass transition temperature and crystallinity may affect deformation and change the elastic modulus when compared to the bulk material. However, size-dependent behavior of elastic moduli could not be generalized across polymers. As for crystalline metal nanoparticles, dislocations were found to influence the mechanical properties of nanoparticles, contradicting the conventional view that dislocations are absent in crystalline nanoparticles.

=== Indirect discrimination === Although the Fair Work Act 2009 does not expressly distinguish direct and indirect discrimination as other federal legislation does, and state legislation does, if a rule that is neutral on its face has a disparate impact on one group, this will also be unlawful. For example, in Australian Iron & Steel Pty Ltd v Banovic an employer’s policy for redundancy based on “last in, first off” was held to be indirect discrimination against women, who at that mining workplace has mostly only been recently employed. Similarly in Song v Ainsworth Game Technology Pty Ltd a woman won a claim for indirect discrimination, after she was told she could not work full time, and also use her break time to transfer her child from school to after school care. Such a rule disparately impacted women, especially since it was found that other staff could take cigarette breaks without reducing their work hours.

=== Rutin degradation pathway === The enzyme quercitrinase can be found in Aspergillus flavus. This enzyme hydrolyzes the glycoside quercitrin to release quercetin and L-rhamnose. It is an enzyme in the rutin catabolic pathway.

Sources: en.wikipedia.org

Frequently asked questions

Is cardarine a SARM?

No. Cardarine is GW501516, a PPARδ agonist, while SARMs act on androgen receptors. The two classes are often grouped in informal discussions despite different mechanisms.

Is cardarine approved for human use?

No. It has no approved medical indication in any country. Regulatory agencies have not cleared it for treatment or prevention of any condition.

Why was its development discontinued?

Early clinical work stopped after rodent carcinogenicity findings. Those animal results raised concerns about long-term human risk, although direct human evidence is lacking. The human relevance of the tumors remains an open scientific question.

How does cardarine work in the body?

It binds to and activates PPAR delta, a nuclear receptor that controls expression of genes related to fatty acid oxidation. This mechanism can alter energy metabolism in animal models. It is not a direct stimulant or fat-burning enzyme.

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