Tokyo-based Eisai, citing a U.S. FDA go-ahead, said it would jointly enter a Phase III trial with Biogen ($BIIB) for early-stage Alzheimer’s oral candidate BACE inhibitor E2609, focused on blocking amyloid beta linked to the disease.
The effort will be closely watched for study design and the link to Asia, where a recent Phase III effort by Singapore's TauRx targeting the tau tangle pathology failed to meet its endpoint, and as firms such as Eli Lilly ($LLY) and Pfizer ($PFE) also saw setbacks in advanced amyloid trials in the past 2 years.
Biogen made an unspecified upfront payment to Eisai in 2014 along with potential development milestones for E2609 under a formula to share costs.
At stake for the clinical effort is identifying early-stage patients for a disease that lacks a reliable diagnostic outside of specialized physician assessment with improvement aims for delayed onset measured by questions and other observations.
That focus for the estimated 40 million people currently facing Alzheimer’s or dementia has been used in previous trials in a race for a treatment, as forecasts by patient advocacy groups see an a further onslaught of cases in aging societies in China, Japan and the U.S., among others.
"The study protocol will be a placebo-controlled design in patients with early Alzheimer’s disease where the treatment group will be administered a dosage of 50 mg/day of E2609 with the primary outcome endpoint assessed at 24 months," Eisai said in a release.
"The primary endpoint will be the Clinical Dementia Rating Sum of Boxes (CDR-SB), with routine safety assessment. Following this discussion with the FDA on the Phase III clinical study designs, Eisai and Biogen intend to have similar discussions with the regulatory authorities in Japan and the EU, and to conduct the study as a global, multi-center study."
Eisai said its candidate possibly blocks the beta-secretase cleaving enzyme that produces amyloid beta, making an early intervention likely key and the oral dose attractive over other efforts that rely on intravenous administration.
“We believe that the Phase III clinical study design outline agreed upon will enable us to efficiently conduct studies on BACE inhibitors aimed at realizing preemptive medicine, and will accelerate the development of E2609," Lynn Kramer, chief clinical officer and chief medical officer of the Eisai Neurology Business Group, said in a statement.
Eisai has had earlier success with symptoms of Alzheimer's through Aricept (donepezil), which fell off the patent cliff in 2010 but became the world’s best-selling Alzheimer’s treatment.
- here's the release (PDF)