FDA Gives Green Light to Phase 3 Trials of New Alzheimer’s Drug

BACE inhibitor treats patients with early disease

The FDA has confirmed that there is sufficient data to support the advancement of E2609, an investigational oral beta-secretase–cleaving enzyme (BACE) inhibitor, into phase 3 clinical studies. E2609 is being jointly developed by Eisai Co., Ltd., and Biogen Inc. for the treatment of patients with early Alzheimer’s disease (AD).

By inhibiting BACE, E2609 decreases beta amyloid proteins in the brain, potentially improving symptoms and slowing disease progression.

Based on clinical and preclinical data presented to the FDA at an “end of phase 2” meeting, the FDA confirmed that the data package was sufficient to commence phase 3 studies, and the agency approved the protocol designs for two phase 3 clinical studies. Patients with early AD will be treated with either E2609 (50 mg per day) or placebo, and the primary efficacy endpoint––the Clinical Dementia Rating Sum of Boxes (CDR-SB)––will be assessed at 24 months.

The phase 2 trial of E2609 was a multicenter, randomized, double-blind, placebo-controlled, parallel-group study designed to evaluate the safety of E2609 in patients with early-to-moderate AD (including prodromal AD), with amyloid beta accumulation confirmed by positron emission tomography (PET) screening. The study included three dosages of E2609: 5 mg per day, 15 mg per day, and 50 mg per day. Plasma and cerebrospinal fluid (CSF) amyloid beta levels were measured in patients before they received E2609 and during the study.

The results of this study suggested favorable safety at all doses of E2609, and showed that total amyloid beta levels in the plasma and CSF were reduced in a dose-dependent manner. In addition, according to an analysis of safety and pharmacokinetic/pharmacodynamic data, the optimal dosage of E2609 was identified as 50 mg per day.

Source: Eisai; August 9, 2016.