VEGF reflects on itself
North American researchers have chemically synthesized a d-protein ligand that blocked the binding of VEGF to its receptor in vitro.1
Reflexion Pharmaceuticals Inc. has licensed the compound and thinks it could have better stability and bioavailability than anti-VEGF antibodies that are l-isomer proteins. The company is optimizing its molecule before doing head-to-head comparisons with Lucentis and Avastin in animal models of age-related macular degeneration.
Protein and peptide molecules expressed in all organisms, including recombinant antibodies produced in bacteria, occur only as the left-handed l-isomer and never as the mirror-image, right-handed d-isomer.
Although biologics developers generally have not been concerned with that distinction, protein therapeutics based on the d-isomer should have greater stability and serum half-life than the l-isomer because the d-isomer is not recognized by the body's proteases. The ability to resist proteolytic degradation also raises the possibility of