Bad news for Biogen: Tecfidera sales trend flat in Q3, analyst says

Last quarter, multiple sclerosis pill Tecfidera underperformed expectations, leading maker Biogen ($BIIB) to lower its 2015 forecast. And with sales still lagging into Q3, at least one analyst is doing the same.

So far this quarter, the med's total prescription tally is flat, Leerink Partners analyst Joseph Schwartz wrote in a Tuesday note to clients. And when you project the numbers out till the end of the period, you get a 1% decline quarter over quarter, with U.S. sales of $711 million that don't measure up to the consensus $730 million.

And the med still falls short of expectations if you extrapolate the script trend analysis out through the end of the year, Schwartz noted. By his calculations, Tecfidera will generate $2.79 billion in 2015, compared with the $2.84 billion or so that Wall Street has forecast.

Last quarter brought some rough announcements from the Massachusetts biotech, which acknowledged that an "expected acceleration" hadn't kicked in for the MS-fighter. Tecfidera--which has posted its fair share of top-line leaps since it first launched in 2013--pulled in $883 million for the quarter with $721 million of that coming from the U.S., a performance that spurred the company to take its revenue growth expectations down a notch.

Now, though, new prescriptions are about 10% lower through the quarter to date, Schwartz wrote, compared with a much smaller decline--about 2%--around this time last quarter.

Whether the med's competitors can capitalize on its slide, though, remains to be seen. Both Gilenya from Novartis ($NVS) and Aubagio from Sanofi ($SNY) compete in the realm of oral MS therapies, and Tecfidera currently leads them both, despite its third-to-market status.

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