This study is intended to assess the safety and tolerance of regadenoson in subjects with renal impairment.

Inclusion Criteria:

• Subject has a Stage III or Stage IV renal impairment based on the National Kidney Foundation (NKF) Kidney Disease Outcomes Quality Initiative (K/DOQI) glomerular filtration rate (GFR) classification
• Subject has a diagnosis of Coronary Artery Disease (CAD) or risk factors for CAD as determined by a current medical diagnosis of at least 2 of the following conditions: Type 2 diabetes, hypertension, hypercholesterolemia, current or history of cigarette smoking (minimum 10 pack-years exposure) or obesity (Body Mass Index (BMI) > 30)
• Subject must abstain from smoking 3 hours prior and 8 hours post study drug administration
• Subject must abstain from any intake of foods and beverages containing a methylated xanthine derivative (i.e. caffeine, theobromine, or methylxanthine) within 12 hours prior to study drug administration through the Follow-Up visit, as these foods may reduce the effects of regadenoson derivative (i.e. caffeine, theobromine, or methylxanthine) within 12 hours prior to study drug administration through the Follow-Up visit, as these foods may reduce the effects of regadenoson

Exclusion Criteria:

• Subject has a history of an additional clinically significant illness, medical condition, or laboratory abnormality within 2 weeks prior to Screening
• Female subject who is pregnant, lactating or of childbearing potential who refuses to use a medically acceptable form of contraception until the Follow-Up visit is complete

Institute and/or Principal Investigator may publish trial data generated at their specific study site after Sponsor publication of the multi-center data. Sponsor must receive a site's manuscript at least 30 days prior to publication to ensure that no confidential information of Sponsor is included in the document. Sponsor may delay the publication for an additional 60 days to seek patent protection.