FIESTA Study

What is this study?

FIESTA is a clinical trial evaluating the safety and efficacy of PDE-5 inhibitor (tadalafil) as a treatment for early stages of Alzheimer's disease. This is an interventional study using a variety of methods to observe the effects of tadalafil in individuals diagnosed with early-stage Alzheimer's disease or Mild Cognitive Impairment.

Phosphodiesterase-5 (PDE-5) enzyme inhibitors are currently licensed for arterial pulmonary hypertension and erectile dysfunction. PDE-5 inhibitors have demonstrated ability in crossing over to the brain and increasing cerebral blood flow. They demonstrate potential as an effective treatment for Alzheimer's disease, and this study will be observing the effects of this treatment.

This is a double-blind study with two groups - neither you nor the investigator will know which group you are in. One group will receive the study drug (tadalafil) and the other will receive a placebo (dummy drug). You will take the drug orally, once a day. You have a 50% chance of receiving the study drug and a 50% chance of receiving a placebo.

Who are we looking for?

We are looking for participants who:

• Have a diagnosis of early-stage Alzheimer's disease or Mild Cognitive Impairment
• Are aged 50 or older
• Are able to provide informed consent
• Are willing to undergo PET/CT scans, MRI scans, and neuropsychological testing
• Are available for regular study visits throughout the trial period

What the study involves

If you participate in the FIESTA study, you will be asked to:

Screening and Baseline Assessments

• Complete eligibility screening questionnaire
• Undergo baseline medical assessment
• Complete neuropsychological test battery to assess thinking skills

Imaging Procedures

• PET/CT Scan: Positron Emission Tomography/Computed Tomography to measure protein density and distribution in the brain
• MRI Scan: Magnetic Resonance Imaging to assess brain structure and function
• Optional Lumbar Puncture: Cerebrospinal fluid sampling to measure biomarkers

Treatment Phase

• Take study medication (tadalafil or placebo) orally once daily
• Attend regular follow-up visits
• Complete periodic cognitive assessments
• Report any side effects or changes in health

What We're Measuring

The study will assess:

• Inflammation in the brain (microglial activation)
• Abnormal protein deposits (β-amyloid and tau)
• Cerebral blood flow changes
• Cognitive function and memory
• Safety and tolerability of the treatment

Where will this study take place?

This study is being conducted across various sites across the UK. The primary site is:

Division of Neurology
Faculty of Medicine, Imperial College London
Level 5, Burlington Danes
Hammersmith Campus
Du Cane Road
London, W12 0NN

Study visits will take place at this location and affiliated clinical facilities.

What to do if I am interested

If you are interested in participating in the FIESTA study, please complete our online eligibility questionnaire below:

Background Information

About Alzheimer's Disease

Alzheimer's disease is the most common cause of dementia in the elderly population. An estimated 850,000 people in the UK have dementia. AD is pathologically defined by the presence of abnormal proteins in the brain. The density and distribution of these proteins can be measured using Position Emission Tomography (PET) imaging and cerebrospinal fluid (CSF) sampling.

Neuroinflammation in Alzheimer's

Inflammation in the brain (revealed as microglial activation) has been found in AD and other dementias. Neuroinflammatory changes are now implicated in the onset and progression of neurodegeneration and may thus serve as an early disease marker and therapeutic target.

Why PDE-5 Inhibitors?

PDE-5 inhibitors have demonstrated the ability to cross into the brain and increase cerebral blood flow. Improved blood flow to the brain may help reduce inflammation, support neuronal function, and potentially slow the progression of Alzheimer's disease. This study aims to evaluate whether tadalafil can provide therapeutic benefits for people with early-stage AD.

Study Information