Biogen (Nasdaq: BIIB) and Eisai Co., Ltd. (Tokyo, Japan) today announced that Biogen, as part of its Alzheimer’s disease (AD) research portfolio, will contribute four virtual posters that showcase data from its clinical trials with ADUHELM (aducanumab-avwa) injection 100 mg/mL solution at the Alzheimer’s Association International Conference (AAIC), being held in Denver, Colo. and virtually from July 26-30, 2021.
ADUHELM was recently granted accelerated approval by the U.S. Food and Drug Administration (FDA) as a treatment for Alzheimer’s disease. Treatment with ADUHELM should be initiated in patients with mild cognitive impairment or mild dementia stage of disease, the population in which treatment was initiated in clinical trials. There are no safety or effectiveness data on initiating treatment at earlier or later stages of the disease than were studied. This indication is approved under accelerated approval based on reduction in amyloid beta plaques observed in patients treated with ADUHELM. Continued approval for this indication may be contingent upon verification of clinical benefit in confirmatory trial(s).
The accelerated approval of ADUHELM has been granted based on data from clinical trials showing the effect of ADUHELM on reducing amyloid beta plaques, a surrogate biomarker that is reasonably likely to predict clinical benefit, in this case a reduction in clinical decline.
“Our presentations to the dementia research community at AAIC of this robust set of clinical trial data will allow us to engage directly with scientists and neurologists on in-depth analyses of our findings,” said Alfred Sandrock, Jr., M.D., Ph.D., Head of Research and Development at Biogen. “We are looking forward to sharing our analyses on biomarkers, ARIA and safety management, the prespecified clinical endpoints in the Phase 3 ADUHELM trials and more.”
“The clinical trial results Biogen shared about our joint asset, ADUHELM, at AAIC are important as we believe the data will help inform the scientific community as we continue to explore the strong scientific rationale behind the amyloid beta pathway as one of the earliest changes that occur in Alzheimer’s disease,” said Lynn Kramer, M.D., Chief Clinical Officer, Neurology Business Group, Eisai.
ADUHELM Poster Presentations
Item-level Analysis of Clinical Measures in Patients with Early Symptomatic Alzheimer’s Disease Following Treatment with High-dose Aducanumab in the Phase 3 Study EMERGE
A poster presentation about item-level data from the EMERGE trial examines results on the individual items, or domains, that comprised the study’s pre-specified endpoints measuring cognition, function and behavior. This analysis shows consistency of high-dose aducanumab treatment effect across these individual items and domains of the primary, secondary and tertiary clinical endpoints in the Phase 3 trial.
In this data set from EMERGE, treatment effects were observed across all six domains (three cognitive and three functional) measured by Clinical Dementia Rating-Sum of Boxes (CDR-SB), the primary endpoint of the trial. Secondary endpoints of the trial included change from baseline in the Alzheimer’s Disease Assessment Scale – Cognitive Subscale (13 items) (ADAS-Cog13) and the Alzheimer’s Disease Cooperative Study-Activities of Daily Living Inventory (Mild Cognitive Impairment version) (ADCS-ADL- MCI). Treatment effects were observed across ADAS-Cog13 items sensitive to cognitive change in early symptomatic Alzheimer’s disease and across a broad range of items measuring ability to conduct activities of daily living, as measured by ADCS-ADL-MCI.
Treatment was also associated with a reduction in the behavioral and psychiatric symptoms of Alzheimer’s disease, as measured by the Neuropsychiatric Inventory-10 (NPI-10), the tertiary efficacy endpoint of EMERGE.
These results are consistent with the results from the primary analysis of these pre-specified endpoints in EMERGE, endpoints that were selected to measure the broad array of cognitive, functional and behavioral symptoms experienced by individuals with Alzheimer’s disease. The analysis concludes that, in EMERGE, treatment with high-dose aducanumab demonstrated reduced clinical decline evidenced by a statistically significant treatment effect on pre-specified primary and secondary clinical efficacy endpoints compared to placebo.
Reductions in Biomarkers of Alzheimer’s Disease Pathophysiology Following Treatment with Aducanumab Were Associated with Slowing in Clinical Decline
A separate poster presentation examines whether an aducanumab-induced reduction in brain amyloid beta (Aβ) plaques and downstream biomarkers of Alzheimer’s disease pathophysiology are associated with a slowing of clinical decline.
The authors assessed this through three analyses. The first, a group-level analysis, examined the association between treatment effect of aducanumab relative to placebo on brain Aβ plaque levels and clinical decline, as measured by amyloid positron emission tomography (PET) imaging and CDR- SB, respectively, across all aducanumab dose groups in the PRIME, EMERGE and ENGAGE clinical trials. Group-level analyses based on data from these trials demonstrated a positive association between aducanumab treatment effect on brain amyloid beta plaques and clinical measures across dose groups and studies, with the exception of the high-dose group from ENGAGE.
The second set of analyses assessed the relationship between treatment effects of aducanumab on brain Aβ plaque levels, downstream biomarkers of Alzheimer’s disease pathophysiology and clinical measures in participant-level analyses. In EMERGE and PRIME, a greater reduction in brain Aβ plaque levels was associated with less decline across clinical endpoints in each study. In EMERGE, greater reduction in brain Aβ plaque levels was also associated with greater reduction in cerebrospinal fluid (CSF) markers of tau and neurodegeneration as well as less decline on clinical endpoints. Several of these relationships were not apparent in ENGAGE, in which a clinical treatment effect of aducanumab was not observed.
The third analysis showed that a smaller magnitude of clinical decline was observed in patients in PRIME, EMERGE and ENGAGE whose brain Aβ plaque levels were lowered to a threshold considered to be amyloid negative relative to patients who did not reach this threshold. Together, these results are consistent with the hypothesized mechanism of action of aducanumab and support a relationship between aducanumab-induced changes in biomarkers of Alzheimer’s disease pathophysiology and slowing of clinical decline.
