Safety and efficacy of orally administered telmisartan for the treatment of systemic hypertension in cats: Results of a double-blind, placebo-controlled, randomized clinical trial

Background: Information regarding the efficacy of telmisartan for feline systemic arterial hypertension is limited. Objectives: To evaluate the safety and efficacy of PO administered telmisartan solution in hypertensive cats. Animals: Client-owned cats with indirect systolic arterial blood pressure (SBP) of 160-200 mm Hg, based on multiple measurements. Methods: This multicenter trial consisted a 28-day, prospective, randomized, double-blind, placebo-controlled, parallel group, efficacy phase and a 154-day extended-use telmisartan phase. Hypertensive cats were randomly assigned to receive 1.5 mg telmisartan/kg PO q12h for 14 days, followed by 2 mg telmisartan/kg PO q24h, or equivalent volume of placebo. Systolic blood pressure was measured on days 0, 14, and 28. Change in SBP compared to baseline was calculated for days 14 and 28. Telmisartan efficacy was defined as significant decrease in SBP at day 14 compared to placebo and a clinically relevant (>20 mm Hg) decrease in SBP at clay 28. Results: Two-hundred twenty-one cats were included. On day 14, least squares mean (95% confidence interval) SBP decrease was significantly larger in telmisartan-treated (-23.3 mm Hg [-28.2 to -18.3]) versus placebo-treated (-7.5 mm Hg [-13.6 to -1.5]) cats (P = .0005). On day 28, telmisartan treatment resulted in a clinically relevant SBP decrease (-23.9 mm Hg [-27.8 to -20.0]), whereas placebo did not (-11.6 mm Hg [-17.4 to -5.9 mm Hg]). The decrease in SBP persisted over the 6-month trial in telmisartan-treated cats. Conclusions and Clinical Importance: Telmisartan significantly decreased SBP to a clinically relevant extent and was well tolerated in hypertensive cats.