Investigational drug comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-04-15. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
Activation of PPARδ changes transcription of genes involved in fatty acid transport, mitochondrial function, and skeletal muscle fuel preference. In rodent studies, pharmacological PPARδ activation was associated with increased endurance and altered body composition. These findings generated interest in performance enhancement, but species differences and study designs limit direct extrapolation to humans. Small human trials were conducted in the 2000s and later discontinued. The extent to which cardarine produces similar metabolic or performance effects in people remains an open question.
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.
| 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 |
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.
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.
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.
A persistent misconception is that cardarine is a fat-burning drug or a safe alternative to anabolic steroids. No approved therapeutic product exists, and human safety data are limited. The tumor findings in rodents remain a central concern in scientific reviews. Products sold online may contain inaccurate labels, impurities, or different compounds entirely, which complicates any assessment of effects. Independent testing of such products has reported frequent mislabeling. For these reasons, discussions in the literature emphasize risks and unknowns rather than benefits.
== Structure and isoforms == The structure of prolactin is similar to that of growth hormone and placental lactogen. The molecule is folded due to the activity of three disulfide bonds. Significant heterogeneity of the molecule has been described, thus bioassays and immunoassays can give different results due to differing glycosylation, phosphorylation and sulfation, as well as degradation. The non-glycosylated form of prolactin is the dominant form that is secreted by the pituitary gland. The three different sizes of prolactin are:
SNAP-7941 is a drug used in scientific research, which is a selective, non-peptide antagonist at the melanin concentrating hormone receptor MCH1. In initial animal studies it had promising anxiolytic, antidepressant and anorectic effects, but subsequent trial results were disappointing, and the main significance of SNAP-7941 is as the lead compound from which more potent and selective antagonists such as SNAP-94847 were developed, although it continues to be used for research into the function of the MCH1 receptor.
saline implant filled with sterile saline solution. silicone implant filled with viscous silicone gel. structured implants using nested elastomer silicone shells and two saline filled lumen. A fourth type of implant, composite (or alternative-composite) implants, have largely been discontinued. These types featured fillers such as soy oil and polypropylene string. Other discontinued materials include ox cartilage, Terylene wool, ground rubber, silastic rubber, and teflon-silicone prostheses.
Most spectrophotometers are used in the UV and visible regions of the spectrum, and some of these instruments also operate into the near-infrared region as well. The concentration of a protein can be estimated by measuring the OD at 280 nm due to the presence of tryptophan, tyrosine and phenylalanine. This method is not very accurate since the composition of proteins varies greatly and proteins with none of these amino acids do not have maximum absorption at 280 nm. Nucleic acid contamination can also interfere. This method requires a spectrophotometer capable of measuring in the UV region with quartz cuvettes. Ultraviolet-visible (UV-vis) spectroscopy involves energy levels that excite electronic transitions. Absorption of UV-vis light excites molecules that are in ground-states to their excited-states. Visible region 400–700 nm spectrophotometry is used extensively in colorimetry science. It is a known fact that it operates best at the range of 0.2–0.8 O.D. Ink manufacturers, printing companies, textiles vendors, and many more, need the data provided through colorimetry. They take readings in the region of every 5–20 nanometers along the visible region, and produce a spectral reflectance curve or a data stream for alternative presentations. These curves can be used to test a new batch of colorant to check if it makes a match to specifications, e.g., ISO printing standards. Traditional visible region spectrophotometers cannot detect if a colorant or the base material has fluorescence.
Sources: en.wikipedia.org
A scenario is a set of related concepts pertinent to the origin of life (abiogenesis), such as the iron-sulfur world. Many alternative abiogenesis scenarios have been proposed by scientists in a variety of fields from the 1950s onwards in an attempt to explain how the complex mechanisms of life could have come into existence. These include hypothesized ancient environments that might have been favourable for the origin of life, and possible biochemical mechanisms.
==== Malaria ==== The President's Malaria Initiative, started with help from George W. Bush, has contributed to a more than 60% reduction in malaria deaths, saved 7.6 million lives, and prevented 1.5 billion malaria cases globally between 2000 and 2019. PMI has supported malaria prevention and control for over 500 million at-risk people in Africa. However, the USAID funding of PMI has been cut an estimated 47% as of June 2025. In countries such as the Democratic Republic of the Congo (DRC), these funds had supported the supply of antimalarial drugs to numerous health zones, including preventive treatments for pregnant women. Health officials in the DRC reported that the effects of these cuts were already being felt, with increased risk of severe illness and death from malaria among vulnerable populations. Former aid workers and experts also expressed concern that reduced funding undermined disease surveillance systems that help detect malaria and other outbreaks early. Such surveillance not only protects affected countries but also contributes to U.S. health security by limiting the global spread of disease. Aid organizations also highlighted how these cuts create a "vicious cycle," with malnutrition and malaria reinforcing one another. Reductions in U.S. support for nutrition programs increase children's vulnerability to malaria and other diseases, while higher malaria infections can worsen malnutrition.
There is, however, a possibility that CD4+ T lymphocytes are involved in an aberrant way, since HLA-B27 appears to have a number of unusual properties, including possibly an ability to interact with T cell receptors in association with CD4 (usually CD8+ cytotoxic T cell with HLAB antigen as it is a MHC class 1 antigen). "Bamboo spine" develops when the outer fibers of the fibrous ring (anulus fibrosus disci intervertebralis) of the intervertebral discs ossify, which results in the formation of marginal syndesmophytes between adjoining vertebrae.
== Interactions == As ribociclib is mainly metabolized by the liver enzyme CYP3A4, inhibitors of this enzyme increase its concentrations in the body and could potentiate side effects and toxicity. Examples of such inhibitors include ketoconazole and similar antifungal drugs, ritonavir, clarithromycin, as well as grapefruit. Conversely, drugs that induce CYP3A4, such as rifampicin and St John's Wort, can decrease ribociclib concentrations. Ribociclib itself is a moderate to strong CYP3A4 inhibitor and can increase concentrations of other drugs that share this metabolism, as has been shown with midazolam. It also inhibits a number of transporter proteins and could thus theoretically interfere with the transport of other drugs in the body. It could also amplify QT prolongation of other drugs such as antiarrhythmics, clarithromycin, and haloperidol.
As noted above, in radioactive decay the half-life is the length of time after which there is a 50% chance that an atom will have undergone nuclear decay. It varies depending on the atom type and isotope, and is usually determined experimentally. See List of nuclides. The current flowing through an RC circuit or RL circuit decays with a half-life of ln(2)RC or ln(2)L/R, respectively. For this example the term half time tends to be used rather than "half-life", but they mean the same thing. In a chemical reaction, the half-life of a species is the time it takes for the concentration of that substance to fall to half of its initial value. In a first-order reaction the half-life of the reactant is ln(2)/λ, where λ (also denoted as k) is the reaction rate constant.
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 a common name for GW501516, a synthetic PPARδ agonist. It is not a steroid or a selective androgen receptor modulator. It was developed and studied as a research compound for metabolic pathways.