These are the sources linked across Kai Peptides. The notes keep the kind of evidence beside each link: an animal experiment, a small human report, a review or an FDA explanation.
A review brings earlier work together; it isn't a new experiment. The FDA page date below tells us when that page was current, not when each substance changed status.
Healing in rat tendons
Staresinic and colleagues, Journal of Orthopaedic Research, 2003.
A study of deliberately cut Achilles tendons in rats reported better healing. It explains interest in repair, but gives no result about people returning to daily tasks.
The limited human BPC-157 record
McGuire and colleagues, Current Reviews in Musculoskeletal Medicine, 2025.
A review describing extensive animal research and very limited human evidence. It helps explain the gap; it does not demonstrate that BPC-157 improves recovery in people.
Two adults in a safety pilot
Lee & Burgess (2025), Alternative Therapies in Health and Medicine.
Two adults who'd already received BPC-157 through a vein took part, with no side effects reported during limited observation. There was no comparison group. The study did not test recovery and cannot settle long-term or uncommon risks.
GHK-Cu skin reports
BioMed Research International (2015), review article.
This review describes small human cream studies. Several underlying reports are not full journal papers. Its summary does not establish that injections help recovery.
Getting an ingredient through skin
Mortazavi, Mohammadi Vadoud and Moghimi, BioImpacts, 2025.
A review of topical GHK, meaning GHK applied to skin. It discusses delivery problems and limited clinical evidence. Cells responding in a dish do not settle what a cream does.
Copper measured in skin samples
Hostynek, Dreher and Maibach, Inflammation Research, 2011.
Researchers applied GHK-Cu to pieces of human skin and measured copper passing through or remaining in the samples. This was a lab experiment, not a study of intact peptide travelling through a person.
KPV in gut cells and mice
Dalmasso and colleagues, Gastroenterology, 2008.
KPV reduced inflammatory signals in cultured cells, with related colitis findings in mice. Human-derived cells are not human participants; this paper cannot establish relief of human gut symptoms.
Protected KPV delivery in mice
Xiao and colleagues, Molecular Therapy, 2017.
Tiny particles and a protective gel carried KPV in mice with colitis. The delivery system belongs to the result. Another preparation would need its own evidence.
FDA safety concerns and withdrawn nominations
U.S. Food and Drug Administration. Page current as of April 22, 2026.
BPC-157, KPV and injectable GHK-Cu appear as withdrawn nominations, with safety concerns still shown. Withdrawal is not clearance or permission to compound. FDA supplies no individual withdrawal dates.
What FDA approval does not cover
U.S. Food and Drug Administration. Consumer explanation of compounded-drug risks.
FDA explains that compounded medicines are not FDA-approved. It does not check their safety, effectiveness or quality before marketing. A prescription does not change that status.
FDA’s closer look at KPV safety
U.S. Food and Drug Administration. KPV safety assessment for its July 2026 advisory committee meeting.
FDA describes gaps in human and animal safety information, with concerns about possible immune reactions and peptide impurities. These are unanswered risks, not measured rates of harm.