A breakthrough regimen in the treatment of hypertension has been approved by the US FDA as a single-tablet combination of two antihypertensive medicines – aliskiren, the first of its kind in more than a decade, and the diuretic hydrochlorothiazide (HCT).

The aliskiren-HCT combination (known as Tekturna HCT in the United States) is the first approved direct renin inhibitor with HCT in a single tablet.

Aliskiren, known as Rasilez outside the US, has been shown to consistently lower blood pressure for 24 hours and beyond. It works by targeting renin and decreasing the activity of the renin system as measured by plasma renin activity (PRA). Renin is a hormone which triggers constriction of the arteries, elevating the blood pressure. By reducing the effects of renin, the drug helps blood vessels to widen so blood pressure is lowered.

HCT, sometimes called a "water pill", is one of the most commonly used medicines for high blood pressure. As a diuretic, it works to lower blood pressure by ridding the body of unneeded water and salt. However, diuretics are also known to increase PRA, so the combination with aliskerin is ideal to neutralize the diuretic effect on PRA.

The combination has been shown by clinical data to offer greater blood pressure reductions than either component alone. The aliskiren-HCT combination is approved for patients not controlled by either medicine alone. Single-tablet combinations simplify treatment by reducing number of pills patients take.

The US approval of aliskiren and HCT combination was based on clinical trials involving more than 2,700 patients treated with aliskiren and HCT.

"Current guidelines call for aggressive treatment of high blood pressure and many patients are still not controlled," said Dr. Alan Gradman from the division of cardiovascular diseases at the Western Pennsylvania Hospital in Pittsburgh, USA. "Tekturna HCT offers patients an effective new treatment option with significant blood pressure reductions and improved convenience, by combining the complementary mechanisms of action of the first direct renin inhibitor and a diuretic in one tablet."

"The rationale for combining a diuretic, which raises plasma renin activity, with Aliskiren, which counters this increase, is compelling and unique, and the firm is very proud to introduce this innovative combination," said Dr. James Shannon, chief medical officer at Novartis Pharma AG.

The long-term potential of aliskiren and direct renin inhibition is being studied in an extensive clinical program known as Aspire Higher, which focuses on the effects of using aliskiren in patients with cardiovascular or kidney disease.

Aliskiren was discovered by Novartis and developed in collaboration with Speedel. Novartis/Speedel won the gold award for aliskiren in The Wall Street Journal’s 7th Annual Technology Innovation Awards contest.