Avonex and similar drugs decrease the rate of MS relapses by 30%, Gilenya by 50%, Tysabri by 70%.

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Gilenya works by a totally new mechanism to block some immune system t-cells from escaping from the lymph nodes.

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If patients switch off BG-12, they might be more likely to try Gilenya than go back to Avonex, meaning a lost sale to Biogen.

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All patients must be observed for six hours after their first dose, because Gilenya can cause a drop in heart rate after it is first given.

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Someone is making millions on black label treatments for MS. Many patients refuse to put their body in harms way by taking a chance on a drug like Gilenya.

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Already approved by the Food and Drug Administration, Gilenya comes in the form of a pill, so its more convenient use is a plus, compared with Copaxone, which is injected.

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Investors have known about Gilenya for years.

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Consider, for example, the reactions of the European Medical Agency (EMA) and Health Canada to the report of the unexplained death of a U.S.-based patient less than 24 hours after receiving the first dose of Gilenya, a relatively new oral treatment for multiple sclerosis.

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Neurologist Samuel Hunter at the Advanced Neurosciences Institute in Franklin, Tennessee, noted in a February 14 article in the Financial Times that there is extensive patient data compiled on Gilenya and that the response of the EMA and Health Canada is likely an overreaction to recent deaths.

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