TB-500 is a synthetic fragment of Thymosin Beta-4, a naturally-occurring protein involved in actin sequestration and cellular migration. BPC-157, in contrast, is derived from a gastric protein and acts on growth factor and nitric oxide pathways.
Researchers often note that TB-500 produces more systemic distribution, while BPC-157 has been studied for more localized soft-tissue effects.
Some research protocols combine both — commonly referred to as a 'Wolverine' stack — to examine synergistic regenerative outcomes.
As with all research peptides, dosing, route, and frequency should be governed by your institutional research protocol.