Learn More About Alzheimer's Disease Research Studies

What Is Alzheimer's Disease, Its Research Studies, and Clinical Trials?

Alzheimer's is a progressive brain disease characterized by a decline in thinking, memory, and behavioral and social functions. According to PubMed, Alzheimer's disease is described as:

"A neurodegenerative disease which has a subtle but gradual onset, and which progresses towards impairment of cognitive functions including language, attention, memory, reasoning, etc."

The number of people living with Alzheimer's disease in the USA is growing every year. According to Alzheimer's Association, more than 6.5 million people aged 65 and older in the USA are suffering from Alzheimer's. The existing figures are expected to rise to approximately 12.7 million by 2050.

The German physician Dr. Alois Alzheimer first described this peculiar disease in 1906, when he followed the mental progress of a 50-year-old patient from her paranoia, memory disturbances, confusion, and aggression until she died five years later.

The discovery and our recognition of Alzheimer's disease are only a little more than a century old. Still, doctors and researchers worldwide are looking for a breakthrough cure to reverse or stop this progressive mental disorder.

Currently, Alzheimer's symptoms such as disorientation, anxiety, and paranoia can be treated to an extent to improve comfort in a patient's life. However, there have been notable advances in treating and diagnosing this disease in the past decade.

Alzheimer's Disease Research Studies

Clinical trials and Alzheimer's disease research studies are the most prominent hope for finding a cure and treatment for this disease. Recruiting trial participants, including those patients who have dementia, their caregivers, as well as healthy volunteers, can contribute to the generation of successful treatments.

For phase II and phase III Alzheimer's disease drug development, many 18 months long placebo-controlled trials have been launched in the past decade. There has been an explosion of Alzheimer's disease research studies that identify potential treatments and causes. The modern-era research studies and clinical trials began in the early 1980s by comparing the neuropsychological deficits associated with Alzheimer's disease with other types of dementias.

Through the 2000s, Alzheimer's disease research studies focused on the prodromal phase. In the current decade, researchers are using biomarkers and other imaging techniques to recognize the disease before the full-blown onset of cognitive decline associated with dementia syndrome.

Why Is Alzheimer's Disease Being Studied Through Clinical Trials?

Alzheimer's disease research studies use human volunteers to determine whether the treatment trials effectively prevent or cure Alzheimer's disease. Despite the growing efforts of clinical trials over the last few years, Alzheimer's disease continues to remain a leading cause of death worldwide.

Alzheimer's disease also enormously impacts healthcare facilities, systems, and community infrastructure. The research community is working to find a solution for the economic, personal, and social costs of the patients, their families and caregivers, and the whole community.

The ineffective clinical trials led to a general agreement that researchers must interfere with the disease's progression prior to its clinical symptoms' onset. Current treatments focus on palliative care to reduce symptoms of neurotransmitter abnormalities resulting from Alzheimer's disease neuropathology.

Alzheimer's disease research studies focus on two important neuropathological hallmarks:

  • Extracellular deposits of amyloid β protein (Aβ)
  • Formation of intraneuronal neurofibrillary tangles or tau tangles.

The most critical approach to Alzheimer's disease research studies is treatment trials, which focus on testing new treatments and drugs. The treatment trials aimed at reducing the symptoms and stopping Alzheimer's disease by testing new drugs and exploring how their combination with existing drugs, different doses, and schedules and variations can affect the delay or reduction of symptoms or treat the disease.

Many Alzheimer's disease clinical studies focus on finding an easy way for physicians to diagnose this disease early so that treatments can begin before the onset of symptoms. Other types of Alzheimer's disease research studies are based on prevention trials to discover certain medications or vitamins that can prevent this disease.

What Are the Types of Treatments Available for Alzheimer's Disease?

Alzheimer's is a complex disease, and it is unlikely that one disease or intervention will treat it in all patients. However, researchers have made several efforts to understand this disease and develop its treatments and medications.

Alzheimer's Disease Treatment

For mild to moderate Alzheimer's disease, the treatment focuses on symptom management so that the patients can live their lives with comfort and independence for as long as possible.


Cholinesterase Inhibitors

The cholinesterase inhibitors like Galantamine, donepezil, and rivastigmine are considered the first-line therapy for mild to moderate Alzheimer's.

These drugs control behavioral and cognitive symptoms associated with Alzheimer's disease. The pharmacological mechanism of all these drugs is slightly different from one another. Still, Alzheimer's disease research studies indicate that these cholinesterase inhibitors prevent the breakdown of acetylcholine in the brain, an important neurotransmitter for thinking and memory. However, these cholinesterase inhibitors gradually lose effectiveness when the disease progresses, and the brain produces lesser acetylcholine.

The most beneficial effect these drugs can provide to the patient is reducing the symptoms and manifestations of the disease. But the debate on whether or not these drugs are effective continues.

Amyloid Beta-Directed Monoclonal Antibody

On June 07, 2021, The US Food and Drug Administration granted accelerated approval for several drugs to manage Alzheimer's disease symptoms. The FDA approved Aducanumab, which reduces amyloid deposits in the human brain and slows the progression of the disease. However, this medication is still not proven to affect the symptoms of Alzheimer's disease in severe stages and progression of dementia.

Aducanumab is a disease-modifying drug for Alzheimer's, which targets the underlying causes of the disease. Aducanumab reduces amyloid plaques in the brain. However, its clinical trials are only conducted in early-stage patients. Researchers are trying to determine whether this medication can affect the decline of cognitive function over time.

Most treatment medicines are effective for patients in early or middle Alzheimer's disease stages. However, none of these medicines can cure the disease.

NMDA Receptor Antagonist

The N-Methyl-D-aspartate receptor antagonist, memantine, is used to treat Alzheimer's disease. The medication isn't a cure, but rather it can decrease its symptoms and allows patients to perform their daily functions a bit longer than they could without medication. For example, memantine can allow late-stage Alzheimer's patients to perform their hygiene tasks independently for a few more months.

The mechanism of action of NMDA receptor antagonists differs from cholinesterase inhibitors, which is why they are often prescribed in combination. The FDA has approved a combination of donepezil and memantine for treating severe Alzheimer's.

Other Therapies

Other therapies make it easier to manage Alzheimer's symptoms when combined with medications.

These include Cognitive Stimulation Therapy, in which groups of patients can participate in exercises that improve memory and cognitive skills.

Reminiscence work involves using keepsakes and photos from childhood to the present day of patients to improve their mood.

Cognitive rehabilitation is a therapy in which a trained professional and relative or friend of the patient enables them to achieve a particular goal or everyday tasks.

What Are Some Recent Breakthrough Clinical Trials for Alzheimer's Disease Research Studies?

Clinical trials were presented at the world's largest forum for dementia and Alzheimer's disease research studies, The Alzheimer's Association International Conference, including drug and non-drug approaches. Dementia research is at a life-changing stage for the patients. Many years of funding and pioneer research are finally resulting in breakthrough ideas that can lead to potential treatments for Alzheimer's disease.

2010: A hypothetical model published by a group of researchers became the focal point of Alzheimer's disease research studies. This model of Alzheimer's biomarkers was received with great interest as it demonstrated the evolution of these biomarkers in relation to the onset and progression of the symptoms and the disease stage. The model is revised periodically to accommodate new research.

2021: The first FDA-approved treatment for Alzheimer's disease, Aducanumab, demonstrates that removing beta-amyloid from the brain reduces cognitive decline.

This therapy approval is a significant development that addresses the underlying cause of Alzheimer's disease. Even though aducanumab is not a cure for Alzheimer's and dementia, it can lead to future appropriate treatments for people diagnosed with early Alzheimer's disease.

2021: Preliminary data from Annovis Bio's Phase II study demonstrated significant improvements in the patients after a month of treatment with Buntanetap. The study is significant as it involves Alzheimer's patients in a mild to moderate stage. After 25 days, the patients showed a 4.4-point improvement in their cognitive functions compared to a 3.3-point improvement using a placebo.

2022: A study from Banner Alzheimer's Institute, Roche, and NIA found that the anti-amyloid drug, crenezumab, did not demonstrate and produce a significant clinical benefit in patients with inherited Alzheimer's disease. The drug did not slow the cognitive decline in early-onset Alzheimer's disease.

This clinical trial looked at this drug's effect in patients carrying faults in a gene called PSEN1, which leads to inherited Alzheimer's disease. The amyloid protein is a key marker for the disease, and several other trials are targeting this protein to explore and treat the disease.

Who Are Some of the Key Opinion Leaders, Researchers, and Institutions Conducting Alzheimer's Disease Clinical Trial Research?

National Alzheimer's Project Act (NAPA)

NAPA creates an opportunity for a coordinated national plan to accelerate Alzheimer's disease-related research. On January 04, 2011, the National Plan for Alzheimer's disease was signed into law and addressed the escalating crisis around Alzheimer's disease, changing the way the whole nation was addressing this disease and other types of dementia before.

The national plan has 6 major goals:

  • Preventing and treating Alzheimer's disease by 2025
  • Enhancing patient care quality
  • Public awareness regarding Alzheimer's
  • Expanding support for Alzheimer's patients and their families
  • Improving clinical data and research
  • Reduce risk factors for the development of Alzheimer's disease and other related dementia.

The National Institute on Aging (NIA)

The NIA is at the forefront of The National Institutes of Health (NIH) 's scientific discovery and clinical research related to Alzheimer's disease. NIA aims its research studies and related conduct to find ways for effectively treating and preventing Alzheimer's disease.

NIA also collaborates with the National Institute of Neurological Disorders and Stroke (NINDS) and works with research centers and institutes to target Alzheimer's disease research studies and fund related projects.

Constantine G. Lyketsos, M.D., M.H.S

Constantine Lyketsos, M.D. is the Elizabeth Plank Althouse Professor of Psychiatry and Behavioral Sciences. His research studies include dementia epidemiology, treatment of neuropsychiatric dementia disorders, and effects of mood disorders and etiology in Alzheimer's patients.