Skep­tics pounce as Bio­gen de­tails pos­i­tive sub­group analy­sis on ad­u­canum­ab — and both sides are dig­ging in

“Ex­hil­a­rat­ing.” “A ma­jor ad­vance.” “A mile­stone achieve­ment.” If one had just tuned in­to the pan­el com­ments on Bio­gen’s pre­sen­ta­tion at CTAD, it would seem that the biotech had an im­pres­sive, dis­ease-mod­i­fy­ing Alzheimer’s drug in ad­u­canum­ab.

But off the stage, re­ac­tions to their ad­mit­ted­ly com­pli­cat­ed dataset and the biotech’s ex­pla­na­tion for res­ur­rect­ing a drug that failed its fu­til­i­ty analy­sis were a lot more mixed, with an­a­lysts con­tin­u­ing to ques­tion whether the ev­i­dence is sub­stan­tial enough to war­rant an FDA ap­proval and rais­ing new doubts on the safe­ty side.

In an in­vestor call lat­er in the day, ex­ecs not­ed that they are not plan­ning an­oth­er study and stood by their in­ten­tion, pub­li­cized in Oc­to­ber to much sur­prise, to sub­mit reg­u­la­to­ry fil­ings based on what they have.

“We don’t file willy nil­ly,” said Al San­drock, head of R&D. “We on­ly go to fil­ing when we be­lieve that there is a ben­e­fit-risk ar­gu­ment based on sci­ence, based on da­ta. And if you look at our his­to­ry, we haven’t done fil­ings right and left with­out good rea­son.”

Bio­gen had a the­o­ry go­ing in­to the Clin­i­cal Tri­als on Alzheimer’s Dis­ease meet­ing.

Unlock this article instantly by becoming a free subscriber.

You’ll get access to free articles each month, plus you can customize what newsletters get delivered to your inbox each week, including breaking news.

SIGN UP LOG IN BECOME A PREMIUM SUBSCRIBER