KPV peptide side effects: what is known about safety
FDA found no human exposure data and no toxicity studies for KPV. What that means for side-effect and safety questions, including the liver.
By the KPV Peptide editorial team · Last reviewed · Editorial review: approved by Ryan DeLauz (bulk sign-off in chat, 2026-11-11)
Short answer
The side effects of KPV in humans are unknown. It has never been given to people in a published study, and FDA identified no toxicity studies, no human pharmacokinetic data and no information on immune reactions [FDA briefing 2026]. FDA lists KPV among compounding substances that may present significant safety risks [FDA 2026].
What FDA looked for and found
FDA’s briefing for the July 2026 advisory committee reviewed the safety record in detail [FDA briefing 2026]:
Safety evidence categories and FDA findings
Evidence type
FDA finding (2026)
Clinical studies assessing safety
None identified
Human pharmacokinetics
None by any route of administration
Acute and repeat-dose toxicity
No studies identified
Genotoxicity
No studies identified
Reproductive and developmental toxicity
No studies identified
Carcinogenicity
No studies identified
Adverse-event reports (FAERS; food and supplement complaints)
No reports retrieved in searches through 3 December 2025
Immunogenicity and aggregation
No information to assess them
FDA concluded that “potential safety risks associated with the use in humans are unknown.” It also judged both KPV and KPV acetate not well characterised, because impurity, aggregate and microbial-quality data were missing from the public record [FDA briefing 2026].
Quality is a safety question too
With no monograph or reference standard, nothing defines what a KPV material must contain. Under acid, alkali or peroxide stress in solution, KPV degrades mainly to a lysine–proline diketopiperazine [Pawar 2015]. FDA noted that the certificate of analysis submitted with the 2026 nomination named one form in its title and a different one in its formula [FDA briefing 2026]. See molecular data for how the forms differ.
Liver and other organ questions
Searches for “KPV peptide side effects liver” have no direct answer. One 2026 study used HepG2 liver cancer cells and measured fat accumulation[Lee 2026]. Studies in skin cells and macrophages likewise measured whether KPV was toxic to the cultured cells [Sung 2025][Bai 2026]. Cell viability in a dish is not organ safety in a person, and no study has measured human liver, kidney or heart function after KPV.
Topical exposure
KPV did not cross excised human skin at detectable levels by passive diffusion; microneedles and iontophoresis increased permeation [Pawar 2017]. FDA noted that low permeation might limit systemic exposure, but whether such methods increase absorption in living skin is unknown [FDA briefing 2026].
Frequently asked questions
Is KPV peptide safe?
Its safety in humans is unknown. FDA found no human exposure data by any route and no nonclinical toxicity studies, and it lists KPV among substances that may present significant safety risks in compounding.
Does KPV peptide affect the liver?
No study has measured liver effects of KPV in people. One cell study used human HepG2 liver cells and measured lipid accumulation. That says nothing about liver safety in humans.
Why do some sites say KPV has no side effects?
Because no adverse events have been reported, which is not the same as being safe. FDA found no case reports, but also no studies that would have detected harm.
References
Pawar K, Kolli CS, Rangari VK et al. (2017). Transdermal Iontophoretic Delivery of Lysine-Proline-Valine (KPV) Peptide Across Microporated Human Skin. J Pharm Sci. PubMed 28343991 · doi:10.1016/j.xphs.2017.03.017[Ex vivo, grade D]
Lee JY, Lee J, Jung WK et al. (2026). Lysine-proline-valine peptide attenuates hepatic lipid accumulation through ROS-dependent regulation of the PPARγ pathway in HepG2 cells. Cytotechnology. PubMed 42064835 · doi:10.1007/s10616-026-00967-z[In vitro, grade D]
Sung J, Ju SY, Park S et al. (2025). Lysine-Proline-Valine peptide mitigates fine dust-induced keratinocyte apoptosis and inflammation by regulating oxidative stress and modulating the MAPK/NF-κB pathway. Tissue Cell. PubMed 40073467 · doi:10.1016/j.tice.2025.102837[In vitro, grade D]
Bai JS, Kim RW, Li Y et al. (2026). Lysine-Proline-Valine attenuates oxidized low-density lipoprotein-induced foam cell formation and inflammatory responses in RAW264.7 macrophages. Tissue Cell. PubMed 42854645 · doi:10.1016/j.tice.2026.104036[In vitro, grade D]
Pawar KR, Mulabagal V, Smith F et al. (2015). Stability-indicating HPLC assay for lysine-proline-valine (KPV) in aqueous solutions and skin homogenates. Biomed Chromatogr. PubMed 25298219 · doi:10.1002/bmc.3347[Analytical, grade D]
U.S. Food and Drug Administration, Pharmacy Compounding Advisory Committee (2026-07-23). FDA Briefing Document: KPV-Related Bulk Drug Substances (KPV (free base) and KPV acetate). Source[retrieved 2026-11-11]
U.S. Food and Drug Administration (2026-04-22). Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Source[retrieved 2026-11-11]