A new angiotensin receptor blocker (ARB), azilsartan medoxomil (Edarbi®, Takeda) has been launched in the UK for the treatment of hypertension. It is the eighth ARB available in the UK and so increases treatment options for hypertensive patients, many of whom are not reaching treatment targets.
Studies involving nearly 6,000 patients with hypertension have shown it lowers blood pressure (BP) significantly more than ramipril, valsartan and olmesartan medoxomil when compared at their maximum doses. It also maintains BP lowering over a 24-hour period.
Data on the new compound were presented by Professor Luis Ruilope, (Hospital 12 de Octubre, Madrid, Spain) at a Takedasponsored symposium during the 22nd European Society of Hypertension (ESH) meeting, held in London from 26th–28th April recently.
In one study with ramipril, azilsartan 80 mg once daily provided a 9/6 mmHg greater reduction in clinic BP than ramipril 10 mg once daily, at six months.
A further trial of azilsartan showed that it effectively reduced ambulatory and trough clinic blood pressure versus valsartan 320 mg daily.
The new agent is well tolerated. The more common reported adverse effects with azilsartan are dizziness, diarrhoea, and small, reversible increases in serum creatinine.
Professor Ruilope suggested that the “robust evidence of improved response rates” with azilsartan may be explained by its binding characteristics, showing a high affinity for and slow dissociation from the AT1 receptor. It is a pro-drug, rapidly hydrolysed to its active component, with a half-life of 11 hours.
Because of its selectivity, it may exert a more potent and sustained blood pressure-lowering effect than existing angiotensin receptor blockers, according to some commentators.
The starting dose of azilsartan 40 mg once daily may be increased to 80 mg daily if a patient’s blood pressure is not controlled. A lower starting dose (20 mg) should be considered in special groups, such as the very elderly or those with mild to moderate hepatic impairment. Azilsartan’s NHS cost is £16.80 for a pack of 28 40 mg tablets.
