Efficacy of long-term oral telmisartan treatment in cats with hypertension: Results of a prospective European clinical trial

Background: Efficacy of telmisartan in treating hypertension (HT) in cats has not been largely investigated. Objective: Telmisartan oral solution effectively controls systolic arterial blood pressure (SABP) in hypertensive cats. Animals: Two-hundred eighty-five client-owned cats with systemic HT. Methods: Prospective, multicenter, placebo-controlled, randomized, double-blinded study. Hypertensive cats diagnosed with SABP >= 160 mmHg and <= 200 mmHg without target-organdamage were randomized (2:1 ratio) to receive 2 mg/kg telmisartan or placebo q24 PO. A 28-day efficacy phase was followed by a 120-day extended use phase. Efficacy was defined as significant difference in mean SABP reduction between telmisartan and placebo on Day 14 and group mean reduction in SABP of > 20 mmHg by telmisartan on Day 28 compared to baseline. Results: Two-hundred fifty-two cats completed the efficacy and 144 cats the extended use phases. Mean SABP reduction at Day 14 differed significantly between groups (P < .001). Telmisartan reduced baseline SABP of 179 mmHg by 19.2 (95% confidence interval [CI]: 15.92-22.52) and 24.6 (95% CI: 21.11-28.14) mmHg at Days 14 and 28. The placebo group baseline SABP of 177 mmHg was reduced by 9.0 (95% CI: 5.30-12.80) and 11.4 (95% CI: 7.94-14.95) mmHg, respectively. Of note, 52% of telmisartan-treated cats had SABP <150 mmHg at Day 28. Mean SABP reduction by telmisartan in severe (>= 180 mmHg) and moderate HT (160-179 mmHg) was comparable and persistent over time. Conclusions and Clinical Importance: Telmisartan solution (PO) was effective in reducing SABP in hypertensive cats with SABP >= 160 mmHg and <= 200 mmHg.