US regulators have given tentative approval to Israeli drugmaker Teva Pharmaceutical Industries’ application for a copycat version of Merck & Co’s Hyzaar, which is used to treat of hypertension and reduce stroke in hypertensive patients.

According to the company, its 50mg/12.5mg and 100mg25mg losartan potassium and hydrochlorothiazide tablets should get full clearance when Hyzaar loses its patent protection in the spring of 2010.

Teva’s American depositary shares closed up $0.21 at $36.14 following yesterday’s announcement, which was welcomed by investors. Hyzaar currently pulls in sales of around $542 million a year.