ARB (telmisartan) — The Cardiometabolic RAAS Inhibitor
Telmisartan is an angiotensin II receptor blocker (ARB) primarily used to treat hypertension. In the context of longevity, it is unique among ARBs for its partial agonism of PPAR-γ, offering dual benefits of blood pressure control and improved metabolic function, including enhanced insulin sensitivity.
Mechanism of Action
Telmisartan selectively blocks the binding of angiotensin II to the AT1 receptor, inhibiting the renin-angiotensin-aldosterone system (RAAS) to reduce vasoconstriction and aldosterone secretion. Uniquely among ARBs, it acts as a partial agonist of the peroxisome proliferator-activated receptor gamma (PPAR-γ). This dual action not only lowers blood pressure but also modulates the expression of genes involved in carbohydrate and lipid metabolism, improving insulin sensitivity and reducing vascular inflammation. It may also attenuate age-related arterial stiffness and cardiac remodeling.
Human Trial Evidence
Extensive human trials support the efficacy of telmisartan in managing hypertension and reducing cardiovascular risk. The ONTARGET trial demonstrated that telmisartan was non-inferior to ramipril in reducing cardiovascular death, myocardial infarction, and stroke in high-risk patients. Other studies have shown its superiority in improving insulin sensitivity and lipid profiles compared to other ARBs. Specific human trials explicitly measuring lifespan extension are lacking.
Dosing Protocol
Typically dosed at 20–80 mg once daily for hypertension and cardiovascular risk reduction. Requires a prescription. It has a long half-life of approximately 24 hours, allowing for consistent 24-hour blood pressure control with a single daily dose.
Safety & Contraindications
Generally well-tolerated. Common adverse effects include dizziness, hypotension, and hyperkalemia. Contraindicated in pregnancy due to teratogenic effects on the fetal RAAS. Caution is advised in patients with severe hepatic impairment or bilateral renal artery stenosis. Regular monitoring of blood pressure, renal function, and serum potassium is recommended.