Eisai has enrolled the first subject in the Phase II/III Tau NexGen clinical trial of its investigational anti-microtubule binding region (MTBR) tau antibody, E2814, for dominantly inherited Alzheimer’s disease (DIAD).

The patient was enrolled at Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU) led by Washington University School of Medicine in St Louis.

Eisai created E2814 through a research partnership with University College London. 

Currently being developed as a disease altering agent for tauopathies such as sporadic AD, the MTBR tau antibody can potentially avert the tau seed spread within the brains of affected individuals.

The Tau NexGen trial will analyse the tolerability, safety, biomarker, and cognitive efficacy of investigational treatments in pre-symptomatic or symptomatic subjects with an AD-causing gene mutation. 

DIAN-TU chose E2814 as the first investigational therapy among anti-tau drugs for the trial in March last year.

Symptomatic subjects will be given anti-amyloid β (Aβ) protofibril antibody lecanemab for a duration of six months and randomised to receive the anti-tau drug or a placebo. 

As amyloid plaques deposit before tau tangles in AD, the trial design permits the researchers to determine whether removal of amyloid clears the way for the efficient functioning of the anti-tau drug.

On obtaining positive data in the primary and secondary endpoints in the assessment two years following trial commencement, the study will be expanded for additional two years to evaluate if the drug can decelerate cognitive decline and has an added impact on tau pathology.

Individuals with DIAD genetic mutations could develop AD and also have chances of developing symptoms at nearly the same age as their affected parents did.