GlaxoSmithKline plc (ADR) (GSK), Gilead Sciences, Inc. (GILD): Did Sarepta Therapeutics Inc (SRPT) Just Knock Out Its DMD Competitor?

There’s also the question mark of what will happen to drisapersen in late-stage trials. Whereas it’s seemingly likely that the FDA is going to accept Sarepta’s mid-stage findings for a new drug application filing sometime early next year, drisapersen is currently being studied in a randomized, double-blind and placebo-controlled 186 patient phase 3 trial with results due out next quarter. Safety hasn’t been a major concern throughout any of these DMD trials, so the more wide-ranging results from a study that’s more than 15 times the size of Sarepta Therapeutics Inc (NASDAQ:SRPT)’s could go a long way to proving the worth of drisapersen. It could also completely bury the drug if its responsiveness in boys drops below, say, 70%.

The battle rages on
The truth is that there could be a market for both drugs in treating DMD, but neither may yet have what it takes. I really like eteplirsen — and so do Wall Street analysts – but it’s also arguably difficult to get fully behind a therapy that worked in such a small patient subset without any further testing. Likewise, there are the what-ifs of approving drisapersen, which may deliver an effectiveness around 70% or slightly better, when you have eteplirsen possibly available, which not only slowed progression of the disease in a higher percentage of mid-stage patients, but actually improved walking distance in mid-stage trials — an almost unfathomable reversal of the disease’s effects.

For now, it still appears that this boxing match has plenty of rounds and punches left to be thrown.

The article Did Sarepta Just Knock Out Its DMD Competitor? originally appeared on Fool.com and is written by Sean Williams.

Fool contributor Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.The Motley Fool recommends Gilead Sciences.

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