Second, the doses are small because the target is a high-affinity intracellular enzyme, not a receptor that needs saturating with milligrams of drug
[DOI] [PMC free article] [PubMed] [Google Scholar] van Praag H., Shubert T., Zhao C., Gage F.H
Liposomal BPC-157+KPV Quicksilver Scientific Liposomal BPC-157 + KPV is an oral, multi-purpose, high absorption peptide formulation of BPC-157, a 15 amino acid derivative of the BPC protein naturally found in the human digestive tract, and KPV, a naturally occurring tripeptide composed of lysine, proline, and valine
Peptides are small proteins, meaning that they are composed of amino acid building blocks that are linked by peptide bonds, but they are fairly small in size
Those diagrams from each paper are above (BPC-157 on the left and PRP on the right)