Details for Patent: 7,662,365

Title:	Polymer conjugates of opioid antagonists
Abstract:	The invention provides polymer conjugates of opioid antagonists comprising a polymer, such as poly(ethylene glycol), covalently attached to an opioid antagonist. The linkage between the polymer and the opioid antagonist is preferably hydrolytically stable. The invention also includes a method of treating one or more side effects associated with the use of opioid analgesics, such as constipation, nausea, or pruritus, by administering a polymer conjugate of the invention.
Inventor(s):	Bentley; Michael David (Huntsville, AL), Roberts; Michael James (Williamsburg, VA), Shen; Xiaoming (Madison, AL), Cheng; Lin (Huntsville, AL)
Assignee:	Nektar Therapeutics (San Carlos, CA)
Filing Date:	Jan 17, 2006
Application Number:	11/332,964
Claims:	1. A polymer conjugate according to the formula: ##STR00009## or pharmaceutically acceptable salt thereof, wherein: Y is allyl; Z is OH; X is amide, amine, carbamate, sulfide, ether, thioether or urea; and POLY is methoxy poly(ethylene glycol), wherein POLY has a molecular weight of from about 100 Da to about 2,000 Da. 2. The polymer conjugate of claim 1, wherein POLY has the formula CH.sub.3O--(CH.sub.2CH.sub.2O).sub.n--CH.sub.2CH.sub.2-- wherein n is from 2 to 45. 3. The polymer conjugate of claim 2, wherein n is from 2 to 20. 4. The polymer conjugate of claim 1, wherein POLY has a molecular weight of from about 100 Da to about 500 Da. 5. The polymer conjugate of claim 1, wherein X is amide. 6. The polymer conjugate of claim 1, wherein X is amine. 7. The polymer conjugate of claim 1, wherein X is carbamate. 8. The polymer conjugate of claim 1, wherein X is sulfide. 9. The polymer conjugate of claim 1, wherein X is ether. 10. The polymer conjugate of claim 1, wherein X is thioether. 11. The polymer conjugate of claim 1, wherein X is urea. 12. A pharmaceutical composition comprising a polymer conjugate and a pharmaceutically acceptable carrier wherein the polymer conjugate has the formula: ##STR00010## or pharmaceutically acceptable salt thereof, wherein: Y is allyl; Z is OH; X is amide, amine, carbamate, sulfide, ether, thioether or urea; and POLY is methoxy poly(ethylene glycol), wherein POLY has a molecular weight of from about 100 Da to about 2,000 Da. 13. The pharmaceutical composition of claim 12, wherein POLY has the formula CH.sub.3O--(CH.sub.2CH.sub.2O).sub.nCH.sub.2CH.sub.2-- wherein n is from 2 to 45. 14. The pharmaceutical composition of claim 12, wherein n is from 2 to 20. 15. The pharmaceutical composition of claim 12, wherein POLY has a molecular weight of from about 100 Da to about 500 Da. 16. The pharmaceutical composition of claim 12, wherein X is amide. 17. The pharmaceutical composition of claim 12, wherein X is amine. 18. The pharmaceutical composition of claim 12, wherein X is carbamate. 19. The pharmaceutical composition of claim 12, wherein X is sulfide. 20. The pharmaceutical composition of claim 12, wherein X is ether. 21. The pharmaceutical composition of claim 12, wherein X is thioether. 22. The pharmaceutical composition of claim 12, wherein X is urea.