Uricase sequences and methods of treatment

Abstract

Described are improved uricase sequences having beneficial effects and methods of treating patients suffering from hyperuricemia.

1 - 12 . (canceled) 
     
     
         13 . A method of reducing serum uric acid levels in a patient in need thereof comprising administering a uricase, wherein the uricase comprises at least one monomer comprising:
 (a) two engineered cysteine residues;   (b) two polyethylene glycol (PEG) molecules, wherein each PEG is conjugated to each unique engineered cysteine residue;   (c) a deletion of a threonine residue at position 2, wherein the position numbering is relative to the amino acid sequence of SEQ ID NO:27; and   (d) a truncation of the C-terminus, wherein the truncation removes an endogenous C-terminal cysteine residue, and wherein the uricase retains enzymatic activity.   
     
     
         14 . The method of  claim 13 , wherein the patient has gout or tumor lysis syndrome. 
     
     
         15 . The method of  claim 14 , wherein the patient has chronic refractory gout and/or tophaceous gout. 
     
     
         16 . The method of  claim 13 , wherein the uricase is administered subcutaneously or intravenously. 
     
     
         17 - 25 . (canceled) 
     
     
         26 . A method of reducing serum uric acid levels in a patient in need thereof, comprising administering a pharmaceutical composition comprising the uricase as recited in  claim 13 . 
     
     
         27 . The method of  claim 26 , wherein the patient has chronic refractory gout, tophaceous gout, and/or tumor lysis syndrome. 
     
     
         28 . The method of  claim 26 , wherein the uricase is administered subcutaneously or intravenously. 
     
     
         29 . (canceled) 
     
     
         30 . A method of reducing uric acid levels in a patient in need thereof comprising administering a uricase comprising SEQ ID NO:1 covalently linked to a polyethylene glycol (PEG) molecule at each cysteine residue, wherein each PEG is maleimide-functionalized PEG-10 with a molecular weight of about 10 kDa. 
     
     
         31 . The method of  claim 13 , wherein the two unique engineered cysteine residues are selected from the following amino acid positions: 11C, 33C, 119C, 120C, 142C, 196C, 238C, 286C, and 289C, wherein the position numbering is relative to the amino acid sequence of SEQ ID NO:27. 
     
     
         32 . The method of  claim 31 , wherein the two unique engineered cysteine residues are located at amino acid positions 11C and 33C. 
     
     
         33 . The method of  claim 13 , wherein the uricase does not comprise an RGD motif. 
     
     
         34 . The method of  claim 13 , wherein the uricase comprises the amino acid sequence of SEQ ID NO:1. 
     
     
         35 . The method of  claim 13 , wherein the PEG molecules each have a molecular weight of about 10 kDa. 
     
     
         36 . The method of  claim 35 , wherein the PEG is maleimide-functionalized PEG-10. 
     
     
         37 . The method of  claim 13 , wherein the uricase comprises a homotetramer.