PF-00489791 is the novel, selective and long-acting phosphodiesterase type 5 (PDE5) inhibitor. PF-00489791 was safe and generally well tolerated in overt diabetic nephropathy patient population. Most common adverse events were mild in severity and included headache and upper gastrointestinal events. PF-00489791 is the first long-acting PDE5 inhibitor to demonstrate significant reduction of albuminuria when added to standard of care therapy in subjects with type 2 diabetes mellitus and overt diabetic nephropathy. In addition, PF-00489791 causes a clinically meaningful and sustained blood pressure lowering in patients with hypertension.