New data backs wider use of flagship Actelion drug

By Ben Hirschler

VIENNA, Sept 2 (Reuters) - Actelion's ATLN.S top-selling drug Tracleer can help less sick patients with pulmonary arterial hypertension (PAH), as well as those with advanced disease, researchers said on Sunday.

The news could unlock a wider market for the treatment by encouraging doctors to screen for patients who might benefit from earlier therapy.

Nazzareno Galie, a cardiologist at the University of Bologna in Italy, said the drug, known generically as bosentan, helped stabilise the condition of patients with Class II PAH and also improved blood flow.

Tracleer is currently only approved for treating patients with Class III or IV PAH, a rare but life-threatening form of hypertension.

In a study involving 185 patients treated for six months, only 3 percent of patients on Tracleer saw their condition worsen significantly against 14 percent on placebo -- a 77 percent relative risk reduction.

The treated group also had a 23 percent improvement in pulmonary vascular resistance, which measures the resistance to blood flow in the lungs.

Raised resistance to blood flow in the lungs is a hallmark of PAH and leads to an extra load on the heart, which ultimately causes heart failure.