New economic modeling reveals that early intervention with Alzheimer’s treatment donanemab increases lifetime societal value by up to 32%, underscoring the critical economic and health stakes of closing the diagnosis gap as U.S. dementia costs approach $818 billion in 2026.
Treatments capable of slowing the progression of Alzheimer’s disease deliver significantly greater health and economic benefits when administered earlier in the disease course, according to research published Oct. 7 in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association. The analysis, conducted by investigators at the USC Schaeffer Center for Health Policy & Economics, evaluates how the timing of anti-amyloid therapy alters long-term outcomes for patients, care partners, and public health programs.
Modeling Lifetime Benefits and Societal Value of Donanemab
Researchers utilized a dynamic microsimulation model drawn from the U.S. Cost of Dementia Project to project the lifetime benefits of treating patients with donanemab, marketed as Kisunla. The modeling examined three distinct scenarios for a cohort closely mirroring participants in a pivotal Phase 3 clinical trial: receiving treatment during the trial, initiating treatment two years earlier in the disease course, and receiving no treatment.
For patients treated during the clinical trial, disease progression was slowed by 29% compared to a placebo after 18 months. These health improvements translated to a lifetime societal value of $104,900 per person. Roughly half of that total stemmed from improved health-related quality of life valued at $52,300, followed by reductions in unpaid caregiving worth $23,800 and medical cost offsets totaling $22,200 that largely benefited Medicaid.
New therapies and diagnostic tools are making it possible to alter the course of Alzheimer’s disease, but they come with considerable costs. Our research suggests that investments in early detection could help ensure that patients start treatments when they’re more likely to provide the greatest benefit to patients and society.
Jack Chapel, lead author, USC Schaeffer scholar and assistant research professor at the USC Price School of Public Policy
How Earlier Intervention and Stronger Efficacy Amplify Economic Returns
Starting anti-amyloid therapy two years sooner than the clinical trial baseline alters the economic calculus substantially. By slowing cognitive decline earlier in the disease process, earlier treatment increased lifetime societal value by 32% to reach $138,300 per person. When incorporating emerging evidence suggesting that earlier intervention could produce even stronger slowing effects, the estimated lifetime value rose 71% above the clinical trial group to $179,400.
Annual Medicaid cost offsets also shifted based on timing. Treatment initiated during the trial reduced Medicaid costs by about $1,640 annually, or 13%. Across broader scenarios, researchers noted that annual Medicaid cost offsets from treatment total 13% to 17%, depending on when therapy begins.
Uncertainty regarding the duration of treatment benefits remains a central variable. In a conservative scenario where therapeutic effects last only four years rather than persisting through the remainder of the patient’s life, the estimated lifetime value was cut in half to $49,100. However, starting treatment two years earlier still produced 15% more value, bringing that conservative estimate to $56,400.
Closing the Diagnosis Gap and Expanding Future Treatment Pipelines
The economic impact of dementia in the United States is substantial. Alzheimer’s and related dementias will cost the nation an estimated $818 billion in 2026, a figure projected to grow as the population ages. On average, patients receive an Alzheimer’s diagnosis 3.5 years after symptoms first appear, representing a significant delay that limits timely access to disease-modifying care.
Recent diagnostic advancements could help bridge that gap. Several blood-based biomarker tests approved by the FDA over the past year, alongside new digital cognitive assessments, offer practical tools to identify Alzheimer’s in earlier stages. Nevertheless, identifying suitable candidates involves comprehensive clinical evaluation, including cognitive testing, brain imaging, and biomarker analysis, to rule out alternative causes of cognitive decline.
Looking toward future pharmaceutical advances, investigators also modeled potential lifetime benefits from an extensive pipeline featuring more than 150 drugs currently undergoing clinical testing. A hypothetical treatment that slows cognitive progression by 50% would generate an estimated lifetime social value ranging from $208,700 to $276,700, depending on the timing of initiation.
Every year between the first symptoms and a diagnosis is value lost for patients, their families and the public programs that ultimately pay for dementia care.
Jack Chapel, lead author, USC Schaeffer scholar and assistant research professor at the USC Price School of Public Policy
