GSK to pay Actelion up to 1.6 bln for drug rights

By Sam Cage and Sven Egenter

ZURICH (Reuters) - GlaxoSmithKline (GSK.L) could pay Swiss company Actelion (ATLN.VX) up to 3.3 billion Swiss francs (1.6 billion pounds) to develop a promising insomnia drug in the largest biotech partnering deal.

Glaxo, Europe's biggest drugmaker, beat many of the world's top pharmaceuticals companies to partner Actelion's sleeping pill almorexant and the deal sent the Swiss biotech's stock soaring nearly 10 percent on Monday.

"The deal terms already allow significant value to be transferred to shareholders," said Landsbanki Kepler analyst Denise Anderson.

Glaxo, which like other big drugmakers is keen to snap up promising new medicines to bolster its pipeline, had been tipped as a likely partner for almorexant, currently in late-stage clinical development.

But some analysts had questioned whether it would go for the deal as it has the only other similar drug in clinical development, on hold in mid-stage trials.

Other potential partners included Actelion's Swiss neighbour Novartis AG (NOVN.VX), the world's biggest drugmaker Pfizer Inc (PFE.N), Schering Plough SGP.N and Johnson & Johnson (JNJ.N), bankers and analysts have said.

By 10:31 a.m., Actelion shares had dropped back somewhat and were 3.5 percent higher at 54.45 francs. Glaxo shares rose 0.5 percent to 1,197.5 pence.

"Although an announcement of a deal had been expected, the magnitude of the deal and the deal terms had not," Goldman Sachs analyst Stephen McGarry said.