Evaluation of the Clinical Efficacy of Benazepril in the Treatment of Chronic Renal Insufficiency in Cats

Abstract

Abstract Background: Chronic renal insufficiency (CRI) is a common disease in cats. Angiotensin-converting enzyme inhibitors (ACEI) have beneficial effects in humans with CRI by reducing the loss of protein in the urine and increasing life expectancy. Hypothesis: The ACEI benazepril has beneficial effects on survival, clinical variables, or both as compared with placebo in cats with CRI. Animals: 61 cats with naturally occurring CRI. Methods: The cats were enrolled into a prospective, randomized, double-blind, placebo-controlled clinical trial. Cats received placebo or 0.5–1 mg/kg benazepril once daily for up to 6 months. Results: Urine protein/urine creatinine ratios were significantly (P < .05) lower with benazepril as compared with placebo at days 120 and 180. Three cats with placebo and 1 cat with benazepril were removed prematurely from the study because of deterioration of CRI or death. Cats were classified into 4 stages of CRI according to the International Renal Interest Society (IRIS) classification scheme. Incidence rates of cats with IRIS classification stage 2 or stage 3 that remained in stage 2 or 3 without progressing to stage 4 were higher with benazepril (93 ± 5%) as compared with placebo (73 ± 13%). Clinical Importance: These results suggest a potential for benazepril to delay the progression of disease, extend survival time, or both in cats with CRI.