Transdermal patch composition for treating vascular diseases characterized by nitric oxide insufficiency

1. A transdermal patch comprising a therapeutically effective amount of a hydralazine compound of formula I and at least one of isosorbide dinitrate and isosorbide mononitrate, wherein the isosorbide dinitrate is present in an amount to deliver about 20 milligrams per day to about 200 milligrams per day and/or the isosorbide mononitrate is present in an amount to deliver about 10 milligrams per day to about 120 milligrams per day; wherein the hydralazine compound of formula (I) is:

wherein a, b and c are independently a single or double bond; R 1 and R 2 are each independently a hydrogen, an alkyl, an ester or a heterocyclic ring; R 3 and R 4 are each independently a lone pair of electrons or a hydrogen; with the proviso that at least one of R 1 , R 2 , R 3 and R 4 is not a hydrogen.

2. The transdermal patch of claim 1 , further comprising a pharmaceutically acceptable carrier.

3. The transdermal patch of claim 1 , wherein the hydralazine compound is budralazine, cadralazine, dihydralazine, endralazine, hydralazine hydrochloride, pildralazine or todralazine or a pharmaceutically acceptable salt thereof.

4. The transdermal patch of claim 3 , wherein the at least one hydralazine compound is hydralazine hydrochloride.

5. The transdermal patch of claim 4 , wherein the hydralazine hydrochloride is present in an amount to deliver about 30 milligrams to about 300 milligrams per day.

6. The transdermal patch of claim 4 , comprising hydralazine hydrochloride and isosorbide dinitrate.

7. The transdermal patch of claim 4 , comprising hydralazine hydrochloride and isosorbide mononitrate.

8. The transdermal patch of claim 1 , wherein the transdermal patch is a sustained-release transdermal patch.