Acrylic polymers and their use in transdermal drug delivery
The present disclosure is directed to random, acrylic co-polymers that are useful in transdermal applications. Methods of making and using the described co-polymers are also described.
1. A transdermal patch consisting of:
(A) a random co-polymer prepared by a process of combining
(i) a first monomer that is a butyl acrylate monomer, a 2-ethylhexyl acrylate monomer, an octyl acrylate monomer, or an iso-octyl acrylate monomer; and
(ii) at least 18 weight percent, based on the weight of the random co-polymer, of a second monomer that is a methyl methacrylate monomer, a butyl methacrylate, or an isobutyl methacrylate;
in the presence of a polymerization initiator and optionally, an organic solvent;
(B) a therapeutic agent; and
(C) optionally at least one ingredient selected from the group consisting of enhancer, plasticizer, tackifying agent, viscosity modifier, diluent, emollient, anti-irritant, opacifier, pigment, antioxidants, and preservative
wherein the therapeutic agent is dissolved or dispersed in the random co-polymer.
2. The transdermal patch of claim 1 , wherein the random co-polymer is prepared with 20 weight percent, 22.5 weight percent, or 30 weight percent of the second monomer.
3. The transdermal patch of claim 1 , wherein the random co-polymer is prepared with a weight ratio of the first monomer to the second monomer of about 82:18 to about 50:50.
4. The transdermal patch of claim 1 , wherein the polymerization initiator is 2,2′-azodi(2-methylbutyronitrile) (AMBN), dibenzoyl peroxide, lauryol peroxide, or 2,2′-azobisisobutyronitrile (AIBN).
5. The transdermal patch of claim 1 , wherein the organic solvent is ethyl acetate, acetone, hexane, cyclohexane, heptane, toluene, ethanol, or isopropyl alcohol, or a combination thereof.
6. The transdermal patch of claim 1 , wherein the antioxidant is butylated hydroxyanisole (BHA) or butylated hydroxytoluene (BHT).
7. The transdermal patch of claim 1 , wherein the random co-polymer has a Tg of between about −18° C. and −50° C.
8. The transdermal patch of claim 1 , having a shear value of greater than 10 at 8.8 psi.
9. The transdermal patch of claim 1 , wherein the random copolymer is present at a level greater than 60 weight percent of the random co-polymer.
10. The transdermal patch of claim 9 , wherein the random copolymer is present at a level greater than 80 weight percent.
11. The transdermal patch of claim 1 , wherein the plasticizer is present at a level less than 20 weight percent.
12. The transdermal patch of claim 1 , wherein the plasticizer is present at a level less than 10 weight percent.