Market
Neurodegeneration
Drugs to treat the symptoms and effects of neurodegenerative conditions represent a rapidly growing market, at approximately $35 billion. Many of these illnesses are age-related and will have an increased impact over the next twenty years as the elderly population continues to grow.
To date, therapeutic intervention in these diseases has focused on symptomatic treatment such as the cholinesterase inhibitors in Alzheimer’s disease. However, the preferred strategy to combat these diseases is neuroprotection, limiting neurological tissue damage and disease progression. Neuroprotective therapies for central nervous system injury are becoming a primary focus of both pharmaceutical and biotechnology industries.
As new products are approved and overtake for obsolete symptomatic therapies, the neuroprotection market value will grow significantly and constitute a major and important component of the central nervous system market. Market analysis shows that the market value of these therapies will grow from $5.1 billion in year 2005 to $11.5 billion by 2010.
Indications
Alzheimer's disease
Currently, it is estimated that 4.5 million Americans have Alzheimer’s disease (AD). In the seven major pharmaceutical markets (United States, France, Germany, Italy, Spain, the United Kingdom, and Japan) there are 16 million AD patients, a number that is expected to grow to 21 million by 2010. It is also the 8th leading cause of death in the United States and once diagnosed, the average life span of an Alzheimer's patient is eight years.
In the United States alone, direct and indirect annual costs of caring for individuals with AD are at least $100 billion, according to estimates used by the Alzheimer's Association and the National Institute on Aging. Sales for Alzheimer's therapies is estimated to increase to more than $7.8 billion by 2010 in the seven major markets.
The Alzheimer's Society of Canada estimates that 420,600 Canadians over 65 have Alzheimer's disease and related dementias, and 280,000 have Alzheimer's disease. As the population ages, the number of people in Canada with dementia is expected to grow by the year 2031 to more than 750,000.
Schizophrenia-related cognitive impairment
As many as 60 million people worldwide have schizophrenia, according to various surveys. Most people with schizophrenia also suffer from cognitive impairment, although it is independent of the psychotic symptoms of the illness.
In North America, Datamonitor estimates more than two million people have schizophrenia. In Europe, the European Federation of Associations of Families of People with Mental Illness estimates that 6.6 million people suffer from schizophrenia. While there are sales of $18-billion to treat the psychosis associated with schizophrenia, there are no approved drugs treating this cognitive impairment.
Frontotemporal dementia
Frontotemporal dementia (FTD) is a collection of neurodegenerative syndromes characterized clinically by behavioural disturbance, impaired fluency of speech, difficulty in finding words and involuntary movements in some cases. In contrast to AD, FTD generally affects younger patients aged 45-65 years.
FTD is a devastating disease with a median survival of approximately six years from symptom onset and three years after diagnosis in some types. The median time from symptom onset to institutionalization is approximately five years but only one year from formal diagnosis. According to Orphanet, the European portal for rare diseases and orphan drugs, the prevalence for FTD is approximately 3.6-15 per 100,000. Age at onset for FTD is generally earlier than AD and it is referred to as a pre-senile disorder.
FTD is most closely associated with atrophy of the brain involving the frontal lobes, temporal lobes or both, often asymmetrically. Neurochemical evaluations have demonstrated that the cholinergic system is largely intact while dopaminergic and serotoninergic systems are compromised. A variety of neuropathologic changes can be seen including neuronal loss, astrogliosis and loss of synapses but there is no single signature of changes.
Tau abnormalities are seen in several variants of FTD and make up approximately 50% of the FTD population. Neurofibrillary tangles that stain positive for tau are particularly associated with coritcobasal degeneration and progressive supranuclear palsy.
