Eisai Co., Ltd. announced that the Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU), led by Washington University School of Medicine in St. Louis, has enrolled the first subject in the phase II/III study (Tau NexGen study). The study will assess the effect of Eisai's investigational anti-microtubule binding region (MTBR) tau antibody E2814, in dominantly inherited Alzheimer's disease (DIAD).

People who have genetic mutations of DIAD are known to develop Alzheimer's disease (AD) and will likely develop symptoms at around the same age their affected parents did, often in their 50s, 40s or even 30s. The major AD pathologies are amyloid plaque that consists of amyloid beta (Aß) aggregates; neurofibrillary tangles; and intraneuronal aggregates of tau, all of which are believed to spread throughout the brain. The purpose of the Tau NexGen study is to assess the safety, tolerability, biomarker and cognitive efficacy of investigational therapies in pre-symptomatic or symptomatic participants who have an Alzheimer's disease-causing gene mutation.

In March 2021, the DIAN-TU selected E2814, which was created from a research collaboration between Eisai and University College London, as the first investigational medicine among anti-tau drugs for the Tau NexGen study. With increasing evidence from clinical studies showing that targeting amyloid can reduce biomarkers of AD, the Tau NexGen clinical trial leaders selected Eisai's investigational anti-Aß protofibril antibody lecanemab as the background anti-amyloid therapy, and the study design was amended in November 2021. Eisai positions neurology as a key therapeutic area, and it will continue to create innovation in the development of novel medicines based on cutting-edge neurology research as it seeks to contribute further to improving the benefits of affected individuals and their families in diseases with high unmet needs, such as dementia including AD.