PG-008, a fully chemically synthesized peptide, comprises a heterodimer of two cyclic peptides with selective binding affinity for Frizzled and LRP5/6. Unlike Wnt3a, PG-008 lacks lipid moieties, making it highly soluble and eliminating handling difficulties. It exhibits superior activity to Wnt3a in the agonistic activation of ?-catenin pathway.

During the differentiation of iPSCs into definitive endoderm, PG-008 was compared with CHIR99021 and recombinant Wnt3a in terms of differentiation induction efficiency. The results showed that when recombinant Wnt3a (50 ng/mL: approximately 1.3 nM) was used, the efficiency reached around 60%. In contrast, when PG-008 or CHIR99021 was used, the efficiency exceeded 98%. Notably, 1 nM of PG-008 exhibited a differentiation induction efficiency equivalent to that achieved with 3 µM of CHIR99021. PG-008 demonstrated no cytotoxicity up to 10 µM, the highest concentration tested, making it a safer alternative to CHIR99021.