A combination medicine developed by Novartis to treat high blood pressure – billed by some observers as a possible blockbuster product – has been filed for approval in the USA.

Exforge (amlodipine besylate and valsartan), is a fixed-dose combination of the two most-prescribed anti-hypertensives in the marketplace, according to Novartis, and could provide a more effective treatment for the 70% of hypertension patients who do not meet their blood pressure targets using monotherapy.

"With so many patients still uncontrolled, a real need exists for an agent that can help people reach and maintain their blood pressure goal," said James Shannon, head of development at Novartis Pharma.

An application for approval of the product in the European Union was filed last month, although introduction of Exforge in the EU could be delayed until the latter half of 2007 because amlodipine, sold by Pfizer as Norvasc, is still under patent protection.

Novartis could have another blockbuster blood pressure product on its hands if Rasilez (aliskiren), the first in a new class of drugs called rennin inhibitors, gets onto the market.

This drug, which was filed in the USA last week, could bring in multibillion dollar sales at peak, according to some analysts, although others are more wary, noting the drug is addressing a very mature market well-served by cheaper generic medicines.