Actelion has posted a healthy set of figures for the first quarter as its pulmonary arterial hypertension blockbuster Tracleer continues to sell strongly.

Net profit came in at 132.8 million Swiss francs (about $124 millon), a rise of 29.9%, while revenues climbed 23.7% to 501.7 million francs, the majority of which came from Tracleer (bosentan), The latter’s sales climbed 19% on the like, year-earlier period to 405.2 million francs.

Of Actelion’s other products, Ventavis (iloprost), an inhaled therapy for the treatment of PAH, increased 11% to 27.7 million francs, while sales of Zavesca (miglustat), for patients with Gaucher disease for whom enzyme replacement therapy is not a therapeutic option, leapt 69% to 16.9 million francs.

Chief executive Jean-Paul Clozel said “this ongoing strong demand for our medicines positions us well for the future, and allows us to make appropriate investments in a wide range of innovative development candidates”. He added that the introduction of new products, like an improved formulation of the PAH drug epoprostenol, “will also enable us to further leverage our global infrastructure”.

Chief financial officer Andrew Oakley said “I am confident that we will meet our guidance for 2010”. ie revenue growth above 10% and earnings close to 20% up. He added that “our strong balance sheet also enables us to continue the evaluation of external growth opportunities”.

Actelion’s R&D spend in the first quarter went up 21.2% to 116.1 million francs and the Swiss group noted that it has 11 molecules in clinical development, headed by the PAH drugs macitentan and selexipag, clazosentan in non-traumatic aneurismal subarachnoid hemorrhage and almorexant, a sleep disorder drug partnered with GlaxoSmithKline.