Over 55 million people around the world live with dementia, and as the global population ages, that number is expected to nearly triple by 2050. Alzheimer’s disease, the most common form of dementia, accounting for an estimated 60 to 70% of cases, is a neurodegenerative disorder characterized by the accumulation of amyloid plaques and tau neurofibrillary tangles that leads to memory loss and a decline in cognitive abilities so significant, it interferes with daily life and ultimately results in death.
For more than three decades, Johnson & Johnson scientists have been working to better understand the complex biology of Alzheimer’s disease and pioneer new ways to treat it. Today, it’s recognized as a progressive continuum that begins silently with the accumulation of amyloid and tau in the brain, often years before symptoms appear.
Now, the company is closer than ever to reaching three significant goals in the fight against Alzheimer’s disease:
- Identifying the onset of disease in early, potentially more treatable stages
- Driving efforts to delay or prevent disease progression
- Innovating treatments for the late-stage psychiatric symptoms that take a toll not only on patients but their loved ones and caregivers
“We are really pioneers in this space,” says Fiona Elwood, Ph.D., Vice President and Neurodegeneration Disease Area Stronghold Leader, Neuroscience, Johnson & Johnson. “Though we’re part of a much bigger community of researchers tackling Alzheimer’s disease, Johnson & Johnson has been at the forefront for many years. Right now, we are experiencing an exciting era of rapid progress and deepening insight into the disease.”
Scientists are beginning to see the impact of artificial intelligence (AI) approaches and big data initiatives, which can provide better insight into the underlying biology of Alzheimer’s disease. The ability to detect and accurately stage the disease is becoming more precise. And investigational therapies that may show potential in slowing its progression are undergoing clinical trials.
“Our goal is to stop the disease before it even starts,” says Elwood. There is still much work to do, but advancements in this space demonstrate that this future is within our reach.” Here’s how Johnson & Johnson is working toward a world without Alzheimer’s disease.
Targeting tau to slow Alzheimer’s disease at its earliest stages
Tau is a protein found in the brain. Under normal circumstances, it helps stabilize the tube-like structure of neurons, which are the messenger cells that facilitate all bodily functions, including breathing, eating, walking and thinking.
In people with Alzheimer’s disease, tau mysteriously spreads and begins to tangle, preventing neurons from communicating with each other and eventually killing them. This change starts in regions of the brain that control memory and then spreads to parts of the brain that control other cognitive abilities and functions.
Research has shown that once tau is released into the space between neurons, it can seed and spread toxic tangles from one brain cell to another. That insight has shaped Johnson & Johnson’s approach: developing a therapy that targets tau outside the neuron—where the damage propagates.
“You can only work in the field of Alzheimer’s disease if you can pick yourself back up, stay curious and think, ‘What have I learned from this?’” says Elwood.
The result of this continued pursuit is an investigational monoclonal antibody designed to bind and neutralize tau before it can spread to other brain cells. In January 2025, the U.S. Food and Drug Administration granted the monoclonal antibody Fast Track designation—which expedites the development and approval process of therapies that can fill a high unmet medical need. A Phase 2b clinical trial of the monoclonal antibody in participants with early Alzheimer’s disease—defined as mild cognitive impairment due to Alzheimer’s and mild Alzheimer’s dementia—is fully enrolled and ongoing.
This isn’t Johnson & Johnson’s only Alzheimer’s program to receive Fast Track designation. In 2024, that distinction was also given to an anti-tau active immunotherapy. This investigational treatment is designed to instruct the body to generate its own antibodies against tau. Once administered, it then crosses the blood-brain barrier to stop tau from spreading. The immunotherapy is currently being investigated in a Phase 2b study in a unique population: those with preclinical disease, meaning they have been found to have evidence of tau pathology but have not yet developed cognitive impairment.
“It’s really a question of, ‘How can we help as many patients as possible as soon as possible?’” says Gayle Wittenberg, Ph.D., Vice President of Precision Measures, Neuroscience, Johnson & Johnson. “Because while patients are waiting, they’re also progressing. Which means time is of the essence.”
Identifying biomarkers to detect the disease
Measuring cognition is a challenge for both scientists and doctors alike. A multitude of factors can affect thinking, from education level to adequate sleep. Cognition is also what researchers call a “lagging indicator” of Alzheimer’s disease, as cognitive decline only becomes noticeable after tau has already spread in the brain.
Wittenberg first began researching Alzheimer’s disease 15 years ago. “At that time, the ability to identify Alzheimer’s disease during a person’s lifetime was limited,” she says. “A confirmed diagnosis was typically made postmortem.”
Since then, important progress has been made in detecting the disease earlier. Advanced imaging techniques, like positron emission tomography (PET), can now visualize both amyloid and tau biomarkers in the brain in real time. However, PET imaging requires complex procedures and specialized equipment, limiting its accessibility for many patients.
To assist with research efforts, Johnson & Johnson is exploring a simple blood test that could offer an opportunity for patients to delay symptoms before they even start. Microscopic amounts of tau and amyloid detected in a blood sample can help doctors identify people in the earliest stages of disease. A positive test result could one day allow doctors to prescribe preventive treatments or recruit patients into a clinical trial before cognitive decline even starts. “It would be a game changer,” says Wittenberg.
Digital biomarkers are another way Johnson & Johnson is hoping to identify Alzheimer’s disease. Scientists are exploring whether technologies like AI and augmented reality can help detect subtle cognitive or functional changes earlier and more accurately. One area of research focuses on speech patterns—how people talk, not just what they say. Machine learning algorithms are being trained to analyze variations in voice, pitch, tone and word usage over time, with the goal of flagging patterns that may signal early Alzheimer’s-related changes.
Another approach under investigation uses augmented reality via an iPad app to evaluate how someone completes an ordinary task, like locating objects around their house, to test spatial awareness and memory. While these tools are still in development, researchers hope they could one day offer more accessible, frequent ways to assess cognitive health—initially in clinical trials, and eventually at home.
“We’re particularly interested in understanding how early we can identify changes in cognition,” says Wittenberg. “If we can see these changes take place within a year or maybe two years, that would be earlier than the currently available cognition diagnostics allow for today.”
Gathering and sharing data about proteins
Besides tau and amyloid, what other proteins play a significant role in brain diseases like Alzheimer’s disease? Johnson & Johnson is leading an effort alongside Gates Ventures to find out. The Global Neurodegeneration Proteomics Consortium (GNPC), the largest dataset of its kind, consists of more than 40,000 blood and spinal fluid samples gathered from over 20 institutions around the world. Each of these samples contains thousands of proteins—"together, that’s almost 300 million unique protein measurements,” says Wittenberg.
The dataset includes biological samples from Alzheimer’s disease patients and people living with Parkinson’s disease, amyotrophic lateral sclerosis (ALS) and frontal temporal dementia—a collection of disorders caused by progressive nerve cell loss in the brain’s frontal or temporal lobes. Studying the samples and identifying proteins gives researchers an opportunity to understand how these neurodegenerative diseases share connections.
Information from the GNPC could also drastically advance what researchers know about the progression of Alzheimer’s disease. For instance, the three stages of the disease are currently based on the amount of tau and amyloid doctors can see in a patient’s brain. But Alzheimer’s disease is on a continuum, and the thousands of patients represented in the dataset will be at different points along that continuum, providing an unparalleled dataset for researchers to examine.
“It’s going to help us achieve greater accuracy in mapping disease trajectory and increase our understanding of the different points of intervention,” says Wittenberg.
We’re amazed by how far the field of Alzheimer’s disease research has come; it’s taken such a long time.
Treating neuropsychiatric behavior changes
In late-stage Alzheimer’s disease, tau spreads beyond the memory centers of the brain and into broader networks that regulate decision-making, emotion and behavior. Depression, anxiety, aggression and agitation become alarmingly common, affecting up to 97% of patients according to one study. Therapies to minimize these neuropsychiatric changes remain a company priority.
“For caregivers, this is often the most challenging part of the disease because these symptoms are a major source of stress, depression and burnout,“ says Wittenberg. “This is often the tipping point when home care becomes unsustainable, even when that’s what is deeply desired.”
One investigational Johnson & Johnson therapy is being studied for its potential to treat psychosis associated with Alzheimer’s disease and to treat agitation associated with Alzheimer’s disease.
Looking toward the future
Ask any group of people if they have a loved one who has (or had) Alzheimer’s disease, and “you would get a huge number of people raising their hands,” says Elwood. “It’s such a prevalent disease, and it has a large impact on families and caregivers as well.” That helps inspire the innovation happening at Johnson & Johnson, from scientists working in discovery labs to clinicians recruiting and supporting the patients who volunteer for clinical trials.
“We’re amazed by how far the field has come; it’s taken such a long time,” says Elwood.
The company has long been committed to finding ways to treat the spectrum of patients living with Alzheimer’s disease, including prevention of the onset of cognitive decline for those with early biological indicators to people struggling with the psychiatric symptoms of its late stages. But the future has never looked more optimistic.
“We don’t want to overpromise,” says Elwood. “But we’re acutely aware of how much the science has progressed. The arrows are pointing that we’re moving in the right direction.”
