Vascular Reactivity in Chronic Kidney Disease (CKD) Patients Receiving Paricalcitol Versus Placebo

Effects of 19-nor-1α-dihydroxyvitamin D2 (Paricalcitol) Versus Placebo on Oxidative Stress and Vascular Reactivity in CKD Patients

This research is studying how Vitamin D may affect blood vessels reaction to stress and blood levels of substances that may increase blockages in the blood vessels in chronic kidney disease (CKD) patients. Blood vessel health is worsened in CKD and some studies have shown that Vitamin D improves blood vessel health. The type of Vitamin D being used in this study (paricalcitol) is Food and Drug Administration (FDA) approved to treat high parathyroid hormone levels. The purpose of this study is to find out if paricalcitol has other benefits beyond its ability to lower parathyroid hormone levels such as improving the blood vessels reaction to stress and decreasing blood levels of substances that may increase blockages in the blood vessels.

Inclusion Criteria:

• Males or females ≥ 18 years of age at the start of screening
• CKD with eGFR 15-60 mL/min/1.73m2 by MDRD
• Not expected to start dialysis for 4 months
• Serum intact PTH 70-200 pg/mL during screening period
• On stable ACEI/ARB regimen for 30 days prior to screening

Exclusion Criteria:

• History of any of the following diseases:

  • congestive heart failure
  • MI within the last 6 months
  • history of cerebrovascular accident
  • significant valvular disease
  • malignancy

• Currently taking any vitamin D products

• Mean systolic blood pressure values > 190 or diastolic blood pressure values > 100 mm/Hg during the preceding 30 day period prior to screening

• Currently being titrated on therapy with an angiotensin converting enzyme inhibitor or angiotensin receptor blocker

• Two consecutive serum calcium values greater than 10.2 mg/dL or Ca x P > 55 mg2/dL2

• Currently receiving erythropoiesis stimulating agent or intravenous iron therapy

• Pregnant or breastfeeding