Novartis AG’s experimental blood pressure pill aliskiren appears to work well when added to other antihypertensive medicines, according to a new study.

Results of a small phase II trial presented at the European Society of Cardiology congress set an encouraging precedent for late-stage study findings, which the Swiss healthcare group is expected to unveil in two weeks.

If successful, industry analysts believe aliskiren, or SPP 100 as it is also known, could be a multibillion-dollar-a-year seller, rivalling established ACE and ARB inhibitors marketed by Novartis and other big manufacturers.

The medicine is the first in a new class of medicines called renin inhibitors, which act at the initial step in the biochemical cascade that controls blood pressure.

One key component of the new drug’s success will be how well it works with other medicines, since this will allow doctors to tailor drug cocktails to ensure optimal blood pressure control.

Heart doctors got a first glimpse of the drug’s potential from the 23-study, which showed aliskiren on its own resulted in a significant fall in blood pressure after 6 weeks while adding a diuretic produced a further significant extra reduction.

There were no serious side effects when the medicine was given alone or in combination, Dr. Steve Zelekofske of Novartis and colleagues reported.

The new drug could be an important complement to Novartis’s medicine cabinet of High Blood Pressure drugs, which is currently headed up by the ARB drug Diovan, its top-selling treatment with 2004 sales of more than $3 billion.

Adding aliskiren to Diovan could be a big commercial opportunity, especially as the patent clock is ticking on Diovan and the drug loses exclusivity in 2012.

Several other companies are working on renin drugs but their development has been difficult, due to problems in getting sufficient quantities of drug into the bloodstream.

Analysts expect Novartis to unveil the results of trials using aliskiren at a meeting in London on Sept. 20, when it will give financial analysts an update on the progress it is making in terms of its pipeline of new drugs.

Analysts expect phase III data on the drug used alone as a treatment for hypertension and further results from other studies using the drug in combination with existing high-blood pressure medicines.

Novartis has said that it plans to file the drug for approval with regulatory authorities in early 2006, suggesting a market launch could be possible in 2007.

It is also performing tests to prove that aliskiren helps protect the heart and kidneys from long-term damage as a result of high-blood pressure.

Novartis has previously said that the late-stage data would show the drug worked well on its own and that it could also work in combination with other blood pressure pills, like Diovan.