The study was a prospective, randomized, double-blind, placebo-controlled clinical trial involving 16 centers in France, Italy, Switzerland and UK. A total of 162 dogs with class II and III (ISACHC classification)
heart failure caused by chronic valvular disease (CVD) or
dilated cardiomyopathy (DCM) were enrolled.
Benazepril (minimum dosage, 0.25 mg/kg) or placebo were administered orally once daily for up to 34 months, either alone or as add-on
therapy to "standard
therapy" i.e.
diuretics and/or
digoxin and/or
anti-arrhythmic drugs.
RESULTS: The mean survival time (to death or withdrawal from the study due to worsening of
heart failure) was 2.7 times longer in the
benazepril treated group (428 days) as compared with the placebo group (158 days). Differences reached statistical significance (p<0.05 Cox proportional hazards model, 44% reduction in risk). The survival rate after one year was 49% with
benazepril and 20% with placebo.
Benazepril produced a statistically significant (p<0.05) reduction (by 46%) in the risk of worsening of
heart failure (to ISACHC class III) when
therapy was initiated early (in ISACHC class II). In sub-group analyses, a statistically significant (p<0.05) benefit of
benazepril was reached for both survival and worsening endpoints for dogs with CVD (n=125), but not for the small sample of dogs with DCM (37).
Benazepril also improved the exercise tolerance and global clinical condition at day 28 (p<0.05). As compared to the placebo group, dogs treated with
benazepril presented with the same frequency of undesirable clinical events and fewer biochemical disturbances (less frequent increases in plasma
urea or
creatinine and decreases in plasma
potassium).
CONCLUSIONS: