PEG-poly(ortho ester) graft copolymers and pharmaceutical compositions
View Patent ↗This invention relates to graft copolymer delivery vehicles comprising a polyethyleneglycol-poly(ortho ester), and to controlled release pharmaceutical compositions comprising the delivery vehicle and an active agent. The graft copolymer delivery vehicles may be thermogels graft copolymers. The pharmaceutical compositions may be in the form of a topical, syringable, or injectable formulation for local controlled delivery of the active agent.
1. A graft copolymer of Formula L2:
wherein:
L′ is linker comprising the formula
n is an integer from 2 to 500;
p and q are independently integers from 5 to 100;
R 1 is —C 1 -C 4 alkyl;
R and R 3 are each independently H or C 1 -C 4 alkyl; and
each A is R 5 ; where: R 5 is selected from:
where m′ is an integer from 1 to 6.
2. A graft copolymer of Formula III,
wherein:
n is an integer from 2 to 500;
p and q are independently integers from 5 to 100;
R 1 is —C 1 -C 4 alkyl;
R, R 2 and R 3 are each independently H or C 1 -C 4 alkyl; and
each A is R 5 where:
R 5 is selected from:
where m′ is an integer from 1 to 6.
3. The copolymer of claim 2 which is a compound of Formula III where R is H.
4. The copolymer of claim 3 where R 1 is ethyl and R 2 is H.
5. The copolymer of claim 3 where is R 5 is 1,4-cyclohexanedimethylene.
6. The copolymer of claim 2 which is a compound of Formula III where R is H and R 3 is methyl.
7. The copolymer of claim 6 where R 1 is ethyl.
8. The copolymer of claim 6 where R 5 is 1,4-cyclohexanedimethylene.