Abstract: The invention provides formulations and methods of use of furopyridine-based compositions alone and in combination with one or more various second therapeutic agents for the treatment of human disease. The furopyridine composition may include one or more furopyridine species, of which cicletanine is an example. The furopyridines may take various enantiomeric forms, ranging from pure (?) through (?)-dominant, racemic and (+)-dominant to pure (+). Second agents may be any drug useful in combination with a furopyridine in the treatment of diseases such as, cardiovascular disease (hypertension, restenosis, etc.), diabetes, diabetes complications, and polycystic ovarian syndrome. Some of these diseases are associated with endothelial dysfunction and imbalances of prostacyclin or of reactive oxygen species (ROS) or reactive nitrogen species (RNS).