BiOrion’s core technology is based on proprietary PDGF-ß-receptor binding bicyclic peptides, derived from the amino acid binding sequence of its natural ligand PDGF-BB. All the PDGF sub-types are growth factors that regulate cell growth and division and, together with TGF-ß, are the main drivers of fibroblast proliferation and activation during fibrosis. PDGF-ß receptors are specifically expressed in high density on myofibroblasts from different sources, as they are present in all fibrotic organs and tissues. This feature of PDGF-ß-receptors allows cell specific targeting to myofibroblasts.
BiOrion’s bicyclic peptides con be conjugated to functional groups such as radionuclides, for imaging diagnostics, or (existing) antifibrotic drugs, for antifibrotic therapy. Such a bicyclic peptide-drug conjugate binds with medium-affinity to PDGF-ß-receptors without interfering in the PDGF signaling cascade. After binding to the PDGF-ß-receptor the bicyclic peptide-drug conjugate is internalized and has its intended intracellular effect. The PDGF-ß-receptor is therefore only used as a binding target to get internalized and accumulated into the myofibroblast, with no intended effect PDGF signaling.