Roche CEO would not exclude move into rare diseases PARIS (Reuters) - Swiss drugmaker Roche Holding AG would not exclude a move into treatments for rare diseases, its CEO said on Wednesday, even if this represented very small numbers of patients. Chief executive Severin Schwan told a news conference in Paris that Roche's main criteria in terms of disease was not the size of the patient population but how much additional value and medical benefit could be generated for the individual patient. Asked if that meant he did not exclude a move into rare diseases, he said: "We go where the science takes us, wherever it is, independent from the size of the patient population." There has been speculation that Roche might branch out into the lucrative area of rare or so-called orphan diseases after reports it was considering bids for two U.S.-based companies. Shares in biotechnology group Alexion Pharmaceuticals jumped in July after people familiar with the matter said Roche was seeking financing for a possible bid. No offer has emerged. Roche has also been linked to BioMarin Pharmaceuticals, although the company denied last month it was raising financing for a bid following a report. Schwan declined to comment specifically on whether the company was interested in buying Alexion or BioMarin. High prices and lower development and marketing costs of treatments for orphan diseases are drawing the attention of big pharmaceutical companies as older drugs lose patent protection. But Roche's group head of pharmaceuticals said in an interview last month that treating ultra-rare diseases was a distinct business from Roche's current area of expertise. The Basel-based firm is looking to branch out beyond its core cancer drugs and Schwan highlighted the group's focus on autoimmune and inflammatory diseases as well as neuroscience. So in those three areas naturally we are a partner of choice for many companies. But again, if there was an interesting opportunity outside of those established areas, I would be very open to look at it," he said. (Reporting by Natalie Huet. Writing by Caroline Copley.; Editing by Erica Billingham and Jane Merriman)