Aib-BPC-157

Research-Grade

Aib-BPC-157 is a structurally optimized variant of the gastric pentadecapeptide BPC-157 (Body Protection Compound-157) in which one or more L-amino acid residues are replaced with alpha-aminoisobutyric acid (Aib) — a non-proteinogenic, alpha,alpha-disubstituted amino acid that confers exceptional resistance to enzymatic degradation. The parent compound BPC-157 (GEPPPGKPADDAGLV) is a 15-amino-acid fragment of a protein isolated from human gastric juice that has demonstrated remarkable tissue-protective and regenerative properties across dozens of preclinical studies, including accelerated healing of tendons, ligaments, muscle, gut epithelium, and bone. However, native BPC-157 is susceptible to rapid proteolytic cleavage in vivo, limiting its effective half-life and necessitating frequent dosing. The Aib substitution strategy exploits the gem-dimethyl group on the alpha-carbon of Aib, which creates severe steric constraints that prevent peptidases from accessing the peptide backbone at or near the substitution site. This approach has been validated in pharmaceutical peptide design for decades — Aib is present in the natural antibiotic peptaibols and has been incorporated into synthetic analogs of GnRH, somatostatin, and other therapeutic peptides. In the context of BPC-157, Aib substitution at strategically selected positions can increase serum stability by 5-10 fold without disrupting the secondary structure (beta-turn) believed to be essential for receptor engagement. Preclinical studies comparing Aib-BPC-157 to native BPC-157 have reported equivalent or superior wound healing, anti-inflammatory, and gastroprotective effects with reduced dosing frequency. The compound retains the parent peptide's hallmark mechanisms: upregulation of growth hormone receptor expression, modulation of the nitric oxide system, interaction with the FAK-paxillin-AKT pathway, and promotion of angiogenesis through VEGF signaling. Aib-BPC-157 remains an investigational compound with no regulatory approval in any jurisdiction. While it inherits the safety profile considerations of native BPC-157 — which has shown no reported organ toxicity, mutagenicity, or significant adverse effects in published animal studies — the Aib-modified variant has an even thinner evidence base, with limited independent replication of the stability and efficacy claims.