PEGylated recombinant human interferon-ω as a long-acting antiviral agent: structure, antiviral activity and pharmacokinetics.

Recombinant human interferon-ω (rhIFN-ω) exhibits a potent antiviral activity. Because of poor pharmacokinetics (PK) of rhIFN-ω, frequent dosing of rhIFN-ω is necessitated to achieve the sustained antiviral efficacy. PEGylation can efficiently improve the PK of rhIFN-ω while substantially decrease its bioactivity. The structure, antiviral activity and PK of the PEGylated rhIFN-ω were measured to establish their relationship with PEGylation sites, polyethylene glycol (PEG) mass and PEG structure. Accordingly, N-terminus and the lysine residues were selected as the PEGylation sites. PEGs with Mw of 20kDa and 40kDa were used to investigate the effect of PEG mass. Linear and branched PEGs were used to investigate the effect of PEG structure. PEGylation decreased the antiviral activity of rhIFN-ω and improved its PK. The PEGylation sites determine the bioactivity of the PEGylated rhIFN-ω and the conjugated PEG mass determines the PK. N-terminally PEGylated rhIFN-ω with 40kDa linear PEG maintains 21.7% of the rhIFN-ω antiviral activity with a half-life of 139.6h. Thus, N-terminally PEGylated rhIFN-ω with linear 40kDa PEG is a potential antiviral agent for long-acting treatment of the viral diseases.