Randomized Placebo-Controlled Clinical Trial of a Chewable Formulation of Amlodipine for the Treatment of Hypertension in Client-Owned Cats
Background: There is an unmet clinical need for a cat-specific formulation of mlodipine to treat hypertensive cats.
Objectives: To assess the efficacy of chewable amlodipine tablets in reducing systolic blood pressure (SBP) in cats diagnosed with systemic arterial hypertension.
Animals: Seventy-seven client-owned cats with systemic hypertension were included (median age 14 years).
Methods: The study was randomized, double-blinded, and placebo-controlled. Forty-two cats received 0.125–0.50 mg/kg amlodipine once daily for 28 days; 35 cats received placebo. After 28 days all cats continued with amlodipine for 2–3 months
in an open-label phase. Blood pressure was measured using high definition oscillometry. A responder was defined as a cat showing a decrease of SBP to <150 mmHg at 28 days or a decrease from baseline ≥15%.
Results: Sixty-one cats completed the study. The responder rate was 63% in amlodipine group and 18% in placebo group. Cats receiving amlodipine were 7.9 (95% CI 2.6–24.1) times more likely to be classified as responders when compared to those receiving placebo (P < .001). From a mean (+-SD) baseline value of 181 (+-12) mmHg, SBP decreased to 154 (+-17) mmHg with amlodipine and to 170 (21) mmHg with placebo (P < .001). The voluntary acceptance rate of amlodipine formulation
was 73%.
Conclusions and Clinical Importance: The chewable amlodipine tablet effectively reduced SBP compared with placebo in hypertensive cats, and was well-tolerated. It can be used concomitantly with angiotensin-converting enzyme inhibitors and in cats with chronic kidney disease.
DATE » 07.04.2015
AUTHORS » M. Huhtinen, G. Derre, H.J. Renoldi, M. Rinkinen, K. Adler, J. Aspegren, C. Zemirline, and J. Elliott