The drug was approved by the FDA last year as a 100mg/mL injection for intravenous use in early Alzheimer’s disease: with the FDA requiring a further clinical trial to verify the drug’s clinical benefit.
Patient screening for the ‘Envision’ trial is planned for May 2022. The primary completion date is expected to be approximately four years after the study begins.
Biogen aims to enroll 18% of US participants in the trial from Black/African American and Latinx populations.
“Historically, patients from diverse backgrounds have been poorly represented in Alzheimer’s disease clinical trials, and we are committed to changing this,” said Priya Singhal M.D., M.P.H., Head of Global Safety & Regulatory Sciences and interim Head of Research & Development at Biogen.
“This goal matches the diversity among Americans diagnosed with early Alzheimer’s disease, while at the same time, the trial will generate substantial data to verify the effectiveness of Aduhelm.”
Biogen says it has multiple strategies to help overcome barriers to diverse patient enrollment in Alzheimer’s disease trials, such as the lack of access to medical centers, familiarity with benefit/risk profile of treatment, and financial or logistical burdens.
The Global Alzheimer’s Platform Foundation estimates that clinical trials of Alzheimer’s therapeutics usually only include around 2-3% African American and Latino individuals. It applauds Biogen’s 18% ambition, saying this should become a baseline goal across clinical trials.
“Older African American and Latino Americans are twice and one-and-a-half times more likely, respectively, to have Alzheimer’s or other dementias—so Biogen’s announcement today takes direct aim at addressing inequities in health research for these disproportionately affected communities,” says the organization.
Meanwhile, enrollment will be increased from the previously announced 1,300 to 1,500 people with early Alzheimer’s disease (mild cognitive impairment due to Alzheimer’s disease and mild Alzheimer’s disease), with confirmation of amyloid beta pathology.
Primary and secondary endpoints
The primary endpoint for the global, placebo-controlled trial will be measured by the Clinical Dementia Rating–Sum of Boxes (CDR-SB) at 18 months after treatment initiation with Aduhem.
The CDR-SB endpoint is a validated measure of both cognition and function that is widely used in clinical trials of patients with early symptomatic Alzheimer’s disease, is consistent with ADUHELM’s Phase 3 Emerge and Engage studies.
In addition to the primary endpoint, CDR-SB, secondary endpoints include Alzheimer's Disease Assessment Scale-Cognitive Subscale (ADAS-Cog 13), Alzheimer's Disease Cooperative Study - Activities of Daily Living Inventory - Mild Cognitive Impairment Version (ADCS-ADL-MCI), Integrated Alzheimer's Disease Rating Scale (iADRS), Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory (NPI-10).
Following the Centers for Medicare and Medicaid Services’s (CMS) National Coverage Determination (NCD) draft, which would restrict Medicare coverage of Aduhelm and other amyloid-targeting therapies to patients enrolled in clinical trials, Biogen says it is committed to engaging with CMS to avoid unnecessary duplication of clinical trials and work towards finding a path to offer immediate access to patients.