SLU-PP-332 Side Effects and Benefits: Preclinical Data

What Is SLU-PP-332? An Exercise Mimetic Candidate

SLU-PP-332 is a synthetic acyl hydrazone with no amino acids; PubChem lists it as CID 5338394.^[4] It comes from Thomas Burris’s group and was characterised in 2023 as a pan agonist of the three estrogen related receptors, ERRα, ERRβ and ERRγ, with the highest potency at ERRα.^[1] The “exercise pill” label came from a 2023 University of Florida news release about the mouse studies, not from any clinical result.^[7]

An exercise mimetic is a compound that reproduces some of the molecular effects of exercise without physical activity. SLU-PP-332 is studied as one, alongside other research compounds such as AICAR. For the full chemistry and mechanism review, see the SLU-PP-332 ERR agonist research page.

How SLU-PP-332 Works at the Cellular Level: Estrogen Related Receptors (ERR Receptors)

ERRs belong to the same nuclear receptor family as the estrogen receptors, but despite the name they do not bind estrogen made by the body. They are nuclear receptors that switch on genetic programs and metabolic pathways for mitochondrial function, energy production and oxidative metabolism.^[1][5] Activating ERR receptors is therefore a way to study those pathways in metabolic research. By activating estrogen related receptors, SLU-PP-332 increased mitochondrial function and cellular respiration in a skeletal muscle cell line, raised mitochondrial content (a marker of mitochondrial biogenesis) in mouse muscle, and turned on an acute aerobic exercise gene program in mouse muscle that depended on ERRα.^[1]

Which receptor matters depends on the tissue. The muscle effects needed ERRα, while protection in a heart-failure model ran mainly through ERRγ.^[1][8] The developers say the compound is not selective enough to separate the three receptors’ roles.^[1]

SLU-PP-332 Benefits: Metabolic Benefits in Animal Data

Exercise Endurance and Skeletal Muscle

In male mice, SLU-PP-332 increased type IIa oxidative skeletal muscle fibres and enhanced exercise endurance, and ERRα activation was critical for the endurance effect.^[1] Treated animals ran about 70% longer and 45% further than untreated controls.^[1] The compound did not replace endurance training: on the main exercise marker gene its response was smaller than that of treadmill running, and the two effects added together.^[1] Exercise and SLU-PP-332 switched on some of the same genetic programs in muscle, but the rodent data do not show that muscle endurance or endurance exercise capacity would change in people.

Fat Loss and Body Weight: Does It Burn Fat?

In diet-induced obese mice and leptin-deficient (ob/ob) mice, a model of severe obesity, SLU-PP-332 mimicked exercise benefits on whole-body energy metabolism, raising energy expenditure and fatty acid oxidation. Fat mass accumulation fell, obesity was reduced and insulin sensitivity improved in these models of metabolic syndrome, without changes in food intake.^[2] Glucose tolerance, a measure of blood sugar control, also improved in the obese mice.^[2] These are the animal data behind claims about fat burning, greater fat oxidation, better fat utilization and weight loss. Energy expenditure here means calories used by the mice, not a feeling of more energy. The treated animals were mice; the efficacy data have not been tested in people, and no study has measured weight loss in humans.

Heart, Kidney and Mitochondrial Health

In a pressure-overload model of heart failure, SLU-PP-332 and a related compound improved ejection fraction, reduced fibrosis and increased survival by enhancing cardiac fatty acid metabolism and mitochondrial function.^[8] In old male mice, ERR agonism reversed age-related mitochondrial dysfunction and inflammation in the kidney.^[9] Together these studies cover skeletal and cardiac muscle and kidney: multiple tissue types, all in animals.

Is SLU-PP-332 Oral? Bioavailability and the SLU-PP-915 Successor

Whether SLU-PP-332 is oral is a common question, so the pharmacology matters. The developers describe SLU-PP-332 as lacking oral bioavailability, and the in-vivo efficacy data come from non-oral delivery in mice. That limitation is why the same group built SLU-PP-915, a related pan-ERR agonist that is orally active and enhanced aerobic exercise capacity in animal studies.^[10][11]

Stability data conflict. A 2023 paper from the developers reported good metabolic stability, while a 2026 study measured extremely low solubility and only a moderate half-life in liver microsomes.^[11][12] The chemical series itself began in 2020, when the group converted an ERRβ/γ-selective agonist into pan agonists that also reach ERRα.^[13] None of these pharmacokinetic studies involved people.

Human Clinical Trials: None

No human has received SLU-PP-332 in any published study, and ClinicalTrials.gov lists no SLU-PP-332 clinical trials.^[3] The closest work used human cells: an independent Italian pilot study applied the compound to muscle cells taken from elderly women and reported lower oxidative stress and senescence markers in cells from inactive women.^[14] Two anti-doping laboratories have mapped its metabolites in human liver fractions to build detection methods.^[15][16] A 2026 systematic review concluded that clinical studies are needed to establish efficacy, safety and bioavailability in humans.^[17]

Reports of anecdotal self experimentation online are not safety data. They cannot show what a compound does, and they describe products of unknown identity.

SLU-PP-332 Side Effects and Safety Data

• No human safety data. With no human studies, SLU-PP-332 side effects in people are unknown, and human safety has never been assessed; an absence of reports is not evidence of safety.^[3][17]
• No dedicated toxicology. No toxicology study has been published; tolerability statements come from short efficacy experiments in mice.^[1]
• A flagged chemical linkage. The developers’ 2026 review calls SLU-PP-332 metabolically unstable and notes that its hydrazone linkage is considered problematic in medicinal chemistry because of rapid metabolism and possible toxicity.^[5]
• Poor oral bioavailability. The developers report that it lacks oral bioavailability and built a separate, orally active successor, SLU-PP-915.^[10]
• Solubility and stability. A 2026 paper measured extremely low solubility and only moderate stability in liver microsomes.^[12]
• Broad receptor action. It activates all three ERRs and cannot separate their roles, so the animal data cannot show what it does in tissues that were not studied.^[1]

These points describe serious risks that remain unstudied, not observed harms. The efficacy data themselves are limited: almost all in-vivo work used male mice in small groups, and every in-vivo study includes the developer group.^[17]

Is SLU-PP-332 FDA Approved?

SLU-PP-332 vs Other Exercise Mimetics

SLU-PP-332 is often grouped with AICAR and MOTS-c, which act through AMPK rather than ERRs. WADA lists all three in the same S4.4.1 class of metabolic modulators.^[6] AICAR differs in having human trial data. See AICAR AMPK activator research and AICAR vs MOTS-c.

What SLU-PP-332 Research Does Not Yet Show

• Any human data. None exists.^[3]
• Independent replication in animals. The endurance and metabolic results come from the developer group and its collaborators.^[17]
• Female animals. Almost all in-vivo work used male mice.^[1][2]
• Long-term exposure. The longest published exposure is about two months, in the kidney-aging study.^[9]

These gaps are not arguments against studying SLU-PP-332. They are arguments against overselling it.

SLU-PP-332 for Laboratory Research

Remy Research supplies SLU-PP-332 for in-vitro research as the Genovare SLU-PP-332 25mg AQ pen. The product page carries its batch testing details.