Paricalcitol, a vitamin D analogue, may be an effective adjunctive therapy to renin-agniotensin-aldosterone system inhibitors for treating patients with diabetes who have a high risk for residual kidney problems, findings published in The Lancet indicated.
Paricalcitol (Abbott, Zempler) is currently indicated for treatment of secondary hyperparathyroidism in patients with chronic renal failure.
U.S. and European researchers enrolled 281 patients with type 2 diabetes and albuminuria who were taking angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARB) between February 2007 and October 2008.
They assigned patients to either placebo (n=93), 1 µg paricalcitol (n=93) or 2 µg paricalcitol and measured the percentage change in geometric mean urinary albumin-to-creatinine ratio (UACR) at baseline and 24 weeks.
Patients who received 2 µg paricalcitol experienced an “early, sustained reduction in UACR,” the researchers found (-18% to -28%; P=.014 vs. placebo). Furthermore, reductions in albuminuria were apparent among patients with high dietary sodium intake, a group of patients who often experience resistance to ACE inhibitor and ARB intervention.
“Addition of 2 µg per day paricalcitol to RAAS inhibition safely lowers residual albuminuria in patients with diabetic nephropathy, and could be a novel approach to lower residual renal risk in diabetes,” the researchers wrote.
More clinical trials are needed to determine whether paricalcitol ultimately improves long-term mortality rates and cardiovascular outcomes among these patients.