Preferred embodiments of the present invention are related to novel therapeutic drugs and drug combinations, and associated methods, for treating and/or preventing complications in patients with diabetes, metabolic syndrome, and/or hypertension. More particularly, aspects of the present invention are related to the use of cicletanine as a monotherapy or in combination with other agents for treatment of disease. Cicletanine, as either a monotherapy or in combination with other drugs, may have the form of a non-racemic mixture of the negative (-) and positive (+) enantiomers of cicletanine, or as either the (-) or (+) enantiomer alone.