RT Journal Article SR Electronic T1 Pharmacokinetic and Pharmacodynamic Studies of a Human Serum Albumin-Interferon-α Fusion Protein in Cynomolgus Monkeys JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 540 OP 548 DO 10.1124/jpet.102.037002 VO 303 IS 2 A1 Blaire L. Osborn A1 Henrik S. Olsen A1 Bernardetta Nardelli A1 James H. Murray A1 Joe X. H. Zhou A1 Andrew Garcia A1 Gordon Moody A1 Liubov S. Zaritskaya A1 Cynthia Sung YR 2002 UL http://jpet.aspetjournals.org/content/303/2/540.abstract AB Interferon-α (IFN-α) is indicated for the treatment of certain viral infections including hepatitis B and C, and cancers such as melanoma. The short circulating half-life of unmodified IFN-α makes frequent dosing (daily or three times weekly) over an extended period (6–12 months or more) necessary. To improve the pharmacokinetics of IFN-α and decrease dosing frequency, IFN-α was fused to human serum albumin producing a new protein, Albuferon. In vitro comparisons of Albuferon and IFN-α showed similar antiviral and antiproliferative activities, although Albuferon was less potent on a molar basis than IFN-α. Pharmacokinetic and pharmacodynamic properties of the fusion protein were enhanced in monkeys. After a single intravenous injection (30 μg/kg,) clearance was 0.9 ml/h/kg, and the terminal half-life was 68 h. After 30 μg/kg subcutaneous injection, apparent clearance (clearance divided by bioavailability) was 1.4 ml/h/kg, the terminal half-life was 93 h, and bioavailability was 64%. The rate of clearance of Albuferon was approximately 140-fold slower, and the half-life 18-fold longer, than for IFN-α given by the subcutaneous route in other monkey studies. Sera from Albuferon-treated monkeys demonstrated dose-related antiviral activity for ≥8 days based on an in vitro bioassay, whereas antiviral activity from IFN-α-treated animals was only slightly elevated relative to vehicle on day 0. Significant increases in 2′,5′-oligoadenylate synthetase mRNA relative to IFN-α- or vehicle-treated animals were maintained for ≥10 days after subcutaneous dosing. The improved pharmacokinetics of Albuferon are accompanied by an improved pharmacodynamic response suggesting that Albuferon may offer the benefits of less frequent dosing and a potentially improved efficacy profile compared with IFN-α. The American Society for Pharmacology and Experimental Therapeutics