Claims for Patent: 6,613,355

Summary for Patent: 6,613,355

Title:	Semi-solid delivery vehicle and pharmaceutical compositions
Abstract:	A semi-solid delivery vehicle contains a polyorthoester and an excipient, and a semi-solid pharmaceutical composition contains an active agent and the delivery vehicle. The pharmaceutical composition may be a topical, syringable, or injectable formulation; and is suitable for local delivery of the active agent. Methods of treatment are also disclosed.
Inventor(s):	Ng; Steven Y. (San Francisco, CA), Shen; Hui-Rong (Fremont, CA), Heller; Jorge (Woodside, CA)
Assignee:	A.P. Pharma, Inc. (Redwood City, CA)
Application Number:	09/854,180
Patent Claims:	1. A semi-solid delivery vehicle, comprising: (a) a polyorthoester of formula I or formula II ##STR14## where: R is a bond, --(CH.sub.2).sub.a --, or --(CH.sub.2).sub.b --O--(CH.sub.2).sub.c --; where a is an integer of 1 to 10, and b and c are independently integers of 1 to 5; R* is a C.sub.1-4 alkyl; n is an integer of at least 5; and A is R.sup.1, R.sup.2, R.sup.3, or R.sup.4, where R.sup.1 is: ##STR15## where: p is an integer of 1 to 20; R.sup.5 is hydrogen or C.sub.1-4 alkyl; and R.sup.6 is: ##STR16## where: s is an integer of 0 to 30; t is an integer of 2 to 200; and R.sup.7 is hydrogen or C.sub.1-4 alkyl; ##STR17## where: x is an integer of 0 to 30; y is an integer of 2 to 200; R.sup.8 is hydrogen or C.sub.1-4 alkyl; R.sup.9 and R.sup.10 are independently C.sub.1-12 alkylene; R.sup.11 is hydrogen or C.sub.1-6 alkyl and R.sup.11 is C.sub.1-6 alkyl; or R.sup.11 and R.sup.12 together are C.sub.3-10 alkylene; and R.sup.4 is the residue of a diol containing at least one functional group independently selected from amide, imide, urea, and urethane groups; in which at least 0.1 mol percent of the A units are of the formula R.sup.1, and (b) a pharmaceutically acceptable, polyorthoester-compatible liquid excipient selected from polyethylene glycol ether derivatives having a molecular weight between 200 and 4000, polyethylene glycol copolymers having a molecular weight between 400 and 4000, mono-, di-, or tri-glycerides of a C.sub.2-19 aliphatic carboxylic acid or a mixture of such acids, alkoxylated tetrahydrofurfuryl alcohols and their C.sub.1-4 alkyl ethers and C.sub.2-19 aliphatic carboxylic acid esters, and biocompatible oils. 2. The semi-solid delivery vehicle of claim 1 where the concentration of the polyorthoester ranges from 1% to 99% by weight. 3. The semi-solid delivery vehicle of claim 1 where the polyorthoester has a molecular weight between 1000 and 20,000. 4. The semi-solid delivery vehicle of claim 1 where the fraction of the A units that are of the formula R.sup.1 is between 1 and 90 mol percent. 5. The semi-solid delivery vehicle of claim 1 where the polyorthoester is of formula I, where: none of the units have A equal to R.sup.2 ; R.sup.3 is: ##STR18## where: x is an integer of 0 to 10; y is an integer of 2 to 30; and R.sup.6 is: ##STR19## where: s is an integer of 0 to 10; t is an integer of 2 to 30; and R.sup.5, R.sup.7, and R.sup.8 are independently hydrogen or methyl. 6. The semi-solid delivery vehicle of claim 5 where: R.sup.3 and R.sup.6 are both --(CH.sub.2 --CH.sub.2 --O).sub.2 --(CH.sub.2 --CH.sub.2)--; R.sup.5 is methyl; and p is 1 or 2. 7. The semi-solid delivery vehicle of claim 6 where: R.sup.3 and R.sup.6 are both --(CH.sub.2 --CH.sub.2 --O).sub.9 --(CH.sub.2 --CH.sub.2)--; R.sup.5 is methyl; and p is 1 or 2.