 This study consists of two parts: Part 1 is an open-label, multiple ascending dose MAD study to evaluate the safety, tolerability and pharmacokinetics of KBP-5074 in healthy subjects. The safety and tolerability will be assessed at each dose level before progressing to the next higher dose. Part 2 is an open label, randomized, parallel study to assess the safety and tolerability, the effect of renal dysfunction on the pharmacokinetics of KBP-5074, as well as the PKPD relationship in subjects with mild to moderate renal impairment. 