Investigational drug is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2026-01-17. Numbers and descriptions here follow the published literature rather than marketing material.
Cardarine is not approved for human therapeutic use in any major jurisdiction. It appears on the World Anti-Doping Agency Prohibited List as a PPARδ agonist within the hormone and metabolic modulators category. Sports organizations test for it because it has been detected in athlete samples and seized products. Regulatory actions against marketed research chemical versions have occurred in several countries, though enforcement varies. Availability through unregulated channels complicates oversight.
Analytical laboratories typically identify cardarine and its metabolites using liquid chromatography-tandem mass spectrometry. Urine is a common matrix in anti-doping testing, while blood and tissue may be used in research settings. Detection windows depend on the assay, the sample matrix, and the compound's metabolism. Because cardarine is extensively metabolized, laboratories often target specific metabolites to improve sensitivity and confirmation. Reference standards are required for reliable quantification. Method validation includes checks for selectivity, linearity, and carryover.
Anti-doping laboratories identify GW501516 and related metabolites using liquid chromatography coupled with tandem mass spectrometry. Urine is the most common matrix, though blood and dried blood spots may also be analyzed. The method targets the parent compound and phase I and phase II metabolites, which extend the detection window. Because the substance is prohibited at all times, athletes can be tested outside competition. Detection limits and windows depend on the assay, sample type, and individual metabolism.
Cardarine is frequently described as a fat-burning or endurance-enhancing supplement, but these claims exceed the available evidence. The compound is not a hormone, steroid, or selective androgen receptor modulator. Research articles discuss it as a tool compound for studying PPARδ biology, while anti-doping literature focuses on its abuse and detection. Quality of unapproved products is uncertain, and independent analyses have found impurities or incorrect labeling. Open questions include whether human cancer risk resembles that seen in rodents and how often non-athletes use the substance.
Cardarine has no approved therapeutic indication and is not marketed as a medicine. The World Anti-Doping Agency lists GW501516 as a prohibited substance at all times, covering both in-competition and out-of-competition periods. National laws vary: some countries treat it as an unapproved drug subject to import controls, while others have specific restrictions on sale for human consumption. It is often sold as a research chemical, a label that does not imply safety or legality. Enforcement actions have targeted online vendors and shipments.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved for human therapeutic use | No marketing authorization identified in major jurisdictions. |
| Anti-doping class | PPARδ agonist; hormone and metabolic modulators | Listed on the WADA Prohibited List. |
| Common test matrix | Urine | Also blood and tissue in research settings. |
| Typical analytical method | LC-MS/MS | Targets parent compound and metabolites. |
| Major safety signal | Tumor findings in rodents | Human relevance not established; limited human data. |
GW501516 acts as an agonist at peroxisome proliferator-activated receptor delta, a nuclear receptor involved in transcription of genes related to lipid handling and energy use. Activation of PPARδ can shift skeletal muscle toward greater fatty acid oxidation in animal models, which is one reason it drew interest for metabolic disease and exercise research. The exact downstream effects depend on tissue, species, dose, and duration. Human data are sparse, so many proposed benefits remain hypotheses rather than established clinical outcomes.
Laboratory studies have examined GW501516 in cell cultures and rodents for conditions such as dyslipidemia, insulin resistance, and obesity. Some trials in humans were initiated, but development was discontinued after preclinical findings raised concerns about cancer in certain models. Those findings do not prove that the compound causes cancer in people, but they contributed to regulatory caution. Later reviews often describe the evidence as preliminary and insufficient for assessing long-term safety.
In the fitness and bodybuilding literature, cardarine is frequently discussed as an endurance agent or fat-loss compound, although such claims are not supported by robust clinical evidence. Online descriptions often mix animal data, user anecdotes, and marketing language. Researchers who study PPARδ agonists distinguish between receptor activation in controlled experiments and unsupervised use of unverified products. The latter introduces unknown purity, dose, and interactions, making reported experiences difficult to interpret scientifically.
Detection of GW501516 in biological samples generally relies on liquid chromatography coupled with tandem mass spectrometry. Urine is a common matrix in anti-doping analysis, while blood or plasma may be used in research settings. Sample preparation can involve enzymatic hydrolysis, protein precipitation, or solid-phase extraction before instrumental analysis. Because the compound undergoes metabolism, assays may target the parent molecule, one or more metabolites, or both. Detection windows are not fixed; they depend on factors such as dose, route, individual metabolism, and assay sensitivity. Reference standards are required for accurate identification and quantification.
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.
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.
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 the investigational chemical GW501516, also written GW-1516. It was developed as a peroxisome proliferator-activated receptor delta agonist for metabolic conditions such as dyslipidemia. Early research focused on lipid handling and energy use in skeletal muscle and other tissues. The compound was never approved as a medicine. In public discussion, it is often grouped with performance-enhancing substances, although its receptor target differs from that of anabolic steroids or selective androgen receptor modulators. Regulatory and health authorities have issued warnings about its use.
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.
==== Knight Grand Cross of the Order of the Bath (GCB) ==== Military Division General Sir Roger Neil Wheeler, , (475595), late The Royal Irish Regiment. Civil Division Sir Anthony Michael William Battishill, , Chairman, Board of Inland Revenue.
=== Parkinson's disease === In the case of Parkinson's disease, a series of observational studies that consistently suggest a possibly substantial reduction in risk among smokers (and other consumers of tobacco products) has led to longstanding interest among epidemiologists. Non-biological factors that may contribute to such observations include reverse causality (whereby prodromal symptoms of Parkinson's disease may lead some smokers to quit before diagnosis), and personality considerations (people predisposed to Parkinson's disease tend to be relatively risk-averse, and may be less likely to have a history of smoking). Possible existence of a biological effect is supported by a few studies that involved low levels of exposure to nicotine without any active smoking. Another study considered a possible role of nicotine in reducing Parkinson's risk: nicotine stimulates the dopaminergic system of the brain, which is damaged in Parkinson's disease, while other compounds in tobacco smoke inhibit MAO-B, an enzyme which produces oxidative radicals by breaking down dopamine. A data-driven hypothesis that long-term administration of very low doses of nicotine (for example, in an ordinary diet) might provide a degree of neurological protection against Parkinson's disease remains open as a potential preventive strategy.
=== GABA === At GABAergic synapses, the cycle is called the GABA-glutamine cycle. Here the glutamine taken up by neurons is converted to glutamate, which is then metabolized into GABA by glutamate decarboxylase (GAD). Upon release, GABA is taken up into astrocytes via GABA transporters and then catabolized into succinate by the joint actions of GABA transaminase and succinate-semialdehyde dehydrogenase. Glutamine is synthesized from succinate via the TCA cycle, which includes a condensation reaction of oxaloacetate and acetyl-CoA-forming citrate. Then the synthesis of α-ketoglutarate and glutamate occurs, after which glutamate is again metabolized into GABA by GAD. The supply of glutamine to GABAergic neurons is less significant, because these neurons exhibit a larger proportion of reuptake of the released neurotransmitter compared to their glutamatergic counterparts
This caused the "most monumental nonnuclear explosion and fire ever seen from space." However, the Soviet Union did not blame the United States for the attack. In 2009, president Barack Obama declared America's digital infrastructure to be a "strategic national asset," and in May 2010 the Pentagon set up its new U.S. Cyber Command (USCYBERCOM), headed by General Keith B. Alexander, director of the National Security Agency (NSA), to defend American military networks and attack other countries' systems. The EU has set up ENISA (European Union Agency for Network and Information Security) which is headed by Prof. Udo Helmbrecht and there are now further plans to significantly expand ENISA's capabilities. The United Kingdom has also set up a cyber-security and "operations centre" based in Government Communications Headquarters (GCHQ), the British equivalent of the NSA. In the U.S. however, Cyber Command is only set up to protect the military, whereas the government and corporate infrastructures are primarily the responsibility respectively of the Department of Homeland Security and private companies. On 19 June 2010, United States Senator Joe Lieberman (I-CT) introduced a bill called "Protecting Cyberspace as a National Asset Act of 2010", which he co-wrote with Senator Susan Collins (R-ME) and Senator Thomas Carper (D-DE). If signed into law, this controversial bill, which the American media dubbed the "Kill switch bill", would grant the president emergency powers over parts of the Internet.
Sources: en.wikipedia.org
=== Sample condition === The sample should be in good contact with the crucible surface. Therefore, the contact surface of a solid bulk sample should be plane parallel. For DSC measurements with powders, stronger signal might be observed for finer powders due to the enlarged contact surface. The minimum sample mass depends on the transformation to be analyzed. A small sample mass (~10 mg) is sufficient if the released or consumed heat during the transformation is high enough. Heavier samples could be used to obtain transformation associated with low heat release or consumption, as larger samples also enlarge the obtained peaks. However, the increasing sample size might worsen the resolution due to thermal gradients which may evolve during heating.
== Symptoms and signs == Symptoms associated with cardiac myxomas are typically due to the effect of the mass of the tumor obstructing the normal flow of blood within the chambers of the heart. Because pedunculated myxomas are somewhat mobile, symptoms may only occur when the patient is in a particular position. Some symptoms of myxoma may be associated with the release of interleukin 6 (IL-6) by the myxoma. High levels of IL-6 may be associated with a higher risk of embolism of the myxoma. Symptoms of a cardiac myxoma include:
== External links == Media related to Pyridoxine at Wikimedia Commons "Pyridoxine". Drug Information Portal. U.S. National Library of Medicine. Archived from the original on 23 January 2017. "Pyridoxine mass spectrum". Golm Metabolome Database.
Sources: en.wikipedia.org
No. Cardarine has not received approval for human therapeutic use in major jurisdictions. It remains an investigational compound.
It is classified as a PPARδ agonist on the WADA Prohibited List. Anti-doping laboratories can detect it and its metabolites in urine. Its use is banned in competition and usually out of competition.
Rodent studies reported increased tumor incidence at multiple sites. The human relevance remains uncertain, but the findings contributed to discontinuation of development. No long-term human cancer data are available.
Legal status varies by country. It is not approved as a medicine, and it is prohibited in sport. Some jurisdictions restrict import, sale, or possession.