Both drugs aim to clear amyloid plaque buildups from the brain in an effort to slow Alzheimer's cognitive declines. The drugmakers said Wednesday both showed signs they may do that. Lilly's drug displayed consistently better results the longer patients took its drug, while Biogen's showed it yielded stronger efficacy the higher the dose.
While Biogen called its update encouraging, investors were hoping a closely watched middle dose would significantly clear amyloid plaques from the brain and slow Alzheimer's cognitive declines. In the update Wednesday, it individually succeeded on the first, but didn't show statistical significance on two measures of cognition. The stock was down 4.8 percent in early morning trading. (For a real-time stock quote, click here.)
Lilly shares fell 3.3 percent in early trading. (For a real-time stock quote, click here.)
Overall, Biogen Chief Medical Officer Alfred Sandrock said, the 166-patient trial showed the medicine showed efficacy on both measures over the course of the year, and that it increased the higher the dose.
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"The data are completely consistent with and only reinforce what we saw back in March," Biogen Chief Medical Officer Alfred Sandrock said in a telephone conversation, referring to results that drove the company's stock up 11 percent as investors hoped the company was onto a drug that could modify the course of the disease.