Alzheimer’s disease (AD) is the most prevalent cause of dementia in the elderly. It is a chronic neurodegenerative disorder characterized by a progressive loss of cognitive function.
Among people aged 65, 2-3% show signs of the disease, while 25–50% of people aged 85 have symptoms of AD and an even greater number have some of the pathological hallmarks of the disease without the characteristic symptoms. The Alzheimer’s Association estimates there are more than 5 million people in the US and 30 million worldwide suffering with AD, with the number expected to triple by the year 2050.
Current Medicare and Medicaid spending is estimated to exceed $80 billion, with additional costs to American businesses of $61 billion annually.
There is currently no cure for AD. Available medications offer only symptomatic benefit for some patients but do not slow disease progression. Nevertheless, these symptomatic drugs are projected to generate >$6 billion in sales in 2010.
MER5101 would be very competitive in this market by providing an opportunity to arrest the disease at its earliest stages when subjects are expected to derive most benefit from immunotherapy to prevent further disease progression.
AD is characterized by the deposition of amyloid-ß (Aß) protein, formation of plaques, glial activation, and tangles composed of tau protein in the brain. Epidemiologic, pathologic, and genetic evidence indicates that Aß has a pivotal role in the pathogenesis of AD. Animal experiments with transgenic mice have demonstrated the importance of clearing Aß from the brain and its role in improving cognition.
MER5101 is comprised of a fragment of amyloid protein conjugated to an immunogenic carrier and formulated with MAS-1 adjuvant. MER5101 is unique from all the other AD vaccine candidates in clinical development. Studies conducted by Dr Cynthia Lemere in naïve and AD transgenic mice have shown that MER5101:
- significantly reduced amyloid plaque in the brain of animals
- significantly improved cognitive function in older animals
- induced a robust protective immune response towards Aß
- avoided unwanted inflammatory response of the immune system
- maintained immune self tolerance to endogenous Aß thereby avoiding the potential for MER5101 to induce autoimmune disease
- without any systemic toxicity in preclinical studies
These properties established for MER5101, coupled with the clinical safety and immune response established in elderly patients for the core technology with self antigens, indicate that MER5101 is appropriate for treating patients with early stage Alzheimer’s to prevent further disease progression.