Biogen Inc. (BIIB): Tau data in Alzheimer’s is nuanced

Research evidence excerpt

Biogen Inc. (BIIB): Tau data in Alzheimer’s is nuanced

Equity Research

14 July 2026 | 2:45PM EDT

At the Alzheimer’s Association International Conference (AAIC), detailed Phase 2 Salveen Richter, CFA

+1(212)934-4204 |

data of IONS-partnered tau-targeting antisense oligonucleotide diranersen in salveen.richter@gs.com

Goldman Sachs & Co. LLC

Alzheimer’s disease were presented and BIIB hosted a call discussing the results. As

Tommie Reerink, CFA

previously reported, the primary endpoint of dose response on the composite +1(212)357-2470 |

Clinical Dementia Rating–Sum of Boxes (CDR-SB) at week 76 was not achieved, as the tommie.reerink@gs.comGoldman Sachs & Co. LLC

lowest dose (60mg biannually; n=60) performed the best. Shares are trading lower, Shrunatra Mishra

also impacting DNLI, in our view, given debates on clinical meaningfulness and +1(332)245-7673shrunatra.mishra@gs.com|

subsequent readthrough to BIIB’s planned Ph3 study, given: the 26% slowing of Goldman Sachs India SPL

ErdmanCDR-SB decline vs. placebo was not nominally-significant (p=0.12); greater tau Lydia | +1(212)357-6383

reduction did not translate into superior clinical benefit, and the drivers of the lydia.erdman@gs.com Goldman Sachs & Co. LLC

inverse dose relationship remain unclear; the small size of the low dose cohort

Matt Dellatorre, Ph.D.

coupled with baseline imbalances; and the greater benefit on cognitive vs. functional +1(212)855-0830 |

matt.dellatorre@gs.com

measures. Questions from the audience included potential exploration of lower Goldman Sachs & Co. LLC

doses and longer durations, subgroups, the confusional state effects, and the overall Elizabeth Webster, Ph.D.

tau ASO mechanism. We recognize the Phase 3 and commercial outlook will likely +1(212)357-9925elizabeth.webster@gs.com|