It has been five months since Elan, the struggling Irish drugmaker, hired Citigroup to review its strategic options. In the meantime, the world’s biggest pharmaceuticals groups have completed a slew of mega-mergers and a host of smaller deals. Reason enough for rumours of an approach by Lundbeck, a Danish pharma company focused on Elan’s sweet spot of neurological disorders, to send shares in the struggling Irish drugmaker up like a shot.

Unfortunately for Elan’s suffering investors, Lundbeck is an unlikely bidder. Buying Elan, whose shares fell like a rock after Tysabri, its top-selling multiple sclerosis drug, was linked to a deadly brain disease last year, would be a stretch for Lundbeck after its recent acquisition of a US rival. Moreover, with sales last year of just $2.2bn, Lundbeck lacks what Elan needs most: the scale and marketing nous needed to revive Tysabri sales and fund development and commercialistaion of promising new drugs.