Shares in Actelion have taken a thumping after the Swiss biotech posted unimpressive nine-month results and lowered sales expectations for 2012.

Net loss was 180.7 million Swiss francs, compared with income of 359.5 million francs in the like, year-earlier period. The figures were hit by a $577 million provision to cover damages in connection with its legal tussle in the USA with Japan's Asahi Kasei Pharma Corp over the heart disease drug fasudil.

That loss was expected but a 7% decline in revenues to 1.37 billion francs was worse than analysts have forecast. The fall was partly due to the strength of the Swiss currency and increasing competition to its pulmonary arterial hypertension blockbuster Tracleer (bosentan).

Sales for the latter in the nine months actually increased 7% to 1.15 billion francs, but third-quarter Tracleer revenues fell 11% to 356 million francs. The problem for Actelion is that a rival PAH product, Gilead Sciences' Letairis (ambrisentan) is selling well in the USA, boosted in March by the US Food and Drug Administration's decision to approve a change to the label that removed a warning about potential liver injury.

As for the Allschwil-based group’s other products, sales of Ventavis (iloprost), an inhaled therapy for the treatment of PAH, were up 11% (in local currencies) to 82 million francs. Turnover of Zavesca (miglustat), for patients with Gaucher disease for whom enzyme replacement therapy is not a therapeutic option, was up 13% (again in local currencies) to 51.2 million francs, though the rises for these products was driven by price rises.

Chief executive Jean-Paul Clozel said Actelion's products "have continued to perform well in a changing market place" and "this is very satisfactory given the pricing pressure that continues globally" and the competition from Letairis. Chief financial officer Andrew Oakley added that "we are evaluating all possible options to mitigate the effect of currency on our reported results without hampering the support for either our marketed products or clinical development assets".

However, he noted that over the next twelve months "we will also make appropriate capital allocation decisions based on operating performance as well as the outcome of upcoming clinical studies". As far as 2012 sales in local currencies, "we currently foresee slight negative growth in the low-to-mid single digit range, mostly the result of increased pricing pressure globally and increased competitive pressure in the USA".

Investors were spooked by the warning and Actelion shares ended down 9.7% to 30.70 francs, the lowest they have traded at since March last year.