Conjugated polymers with reduced antigenicity, methods of preparation and uses thereof

A pharmaceutical composition comprising a conjugate comprising one or more selected bioactive components from the group consisting of a peptide, a protein and a covalently bound glycoprotein to at least one linear or branched polyethylene wherein said polyethylene glycol, if linear, has a group hydroxyl at the end which is not attached to the component or bioactive components ( "distal end") or, if branched, has a hydroxyl group at each distal end, and wherein said polyethylene glycol is attached to a single bioactive component at a single site polyethylene glycol, and a pharmaceutically acceptable excipient or carrier, wherein the conjugate is 95% pure or more, preferably 98% or more, more preferably 99% or more, or 100%, and wherein said at least one linear or branched polyethylene glycol has a molecular mass of 10 kDa to 30 kDa.