Alzheimer's disease next frontier in research

• Age%2C family history%2C genetics play a role in Alzheimer%27s.
• Just five FDA-approved Alzheimer%27s treatments.
• GE has a new diagnostic drug for Alzheimer%27s

If you think other sectors throw a lot of money at research and development, let me introduce you to the pharmaceutical sector which, according to PhRMA, spent $49 billion in 2012 on researching and developing more than 2,900 compounds.

That might sound like a monstrous amount (and it is!), but in the grand scheme of things there are a number of diseases out there that remain untreated or underserved. The good news is that progress is being made against a number of key diseases, such as hepatitis-C where response rates have shot up with the introduction and promise of FDA-approved and experimental drugs. But the truth remains that there are still thousands of diseases yet to be dealt with; some of which are quite deadly, like Alzheimer's disease.

Based on figures from the Centers for Disease Control and Prevention for 2010, Alzheimer's disease ranked as the sixth leading cause of death in this country, ahead of diabetes (which affects more than 25 million people) and influenza/pneumonia, which is particularly dangerous to infants and the elderly. Yet for all intents and purposes, we don't have a very good understanding at all of what causes Alzheimer's or how to stop it. This leaves the door wide open for big pharma and the biotech community to treat a serious disease and potentially make a fortune in the process.

Let's have a look at some of the risk factors we do know about that can lead to Alzheimer's, see what currently approved medications are leading the charge against this disease, and take a look at what the future might hold for treating Alzheimer's.

The risk factors

According to the Alzheimer's Association, there are three primary factors that have been identified by researchers which can lead to Alzheimer's.

The first is simply advancing age. Every five years over the age of 65 leads to a rough doubling of your chance of developing the disease. Second is family history. Simply put, if someone directly related to you has Alzheimer's disease, your chances of developing Alzheimer's increases as well. Finally, genetic make-up plays a role as well with select genes, such as apolipoprotein E-e4, being identified as raising the likelihood of developing Alzheimer's.

There are other factors which may play a role, but are still being researched. The key suggestion from the Alzheimer's Association to help lower your own potential risk (since many of these are genetic, and thus beyond your control) would be to address issues which regulate your cardiovascular health, such as diabetes, hypertension, high cholesterol, stroke, or heart disease which can lead to poor blood flow to your brain and possibly elevate your risk of developing Alzheimer's.

Treatments: Where we are today

Perhaps no Alzheimer's treatment is more well-known that Pfizer (PFE ) and Eisai's Aricept, which lost patent protection roughly three years ago but still generated residual quarterly income of $52 million for Pfizer in the third-quarter thanks to international sales. Aricept is unique in that, of the five drugs approved to treat the symptoms of Alzheimer's by the Food and Drug Administration, it's approved to treat all stages of the disease. By comparison, the other four therapies are strictly for mild-to-moderate, or moderate-to-severe forms of the disease.

The other name to know here would be Forest Laboratories (FRX ) and its moderate-to-severe drug Namenda. Namenda is pretty big deal since it's the only drug with a specific focus on the severe stages of the disease -- and its $396.3 million in second-quarter sales demonstrate that. Before you get too excited, though, understand that Namenda is on a short life span with patents set to expire on this key drug in 2015.

Treatments: Where we tried to go

Having just five FDA-approved Alzheimer's treatments might give you the wrong impression that big pharma simply doesn't care about researching this disease. That couldn't be further from the truth, but crossing the blood-brain barrier has proven difficult and resulted in a flurry of late stage drug failures.

Last year we saw two high-profile Alzheimer's candidates geared toward binding with amyloid-beta peptides get knocked backward in bapineuzumab and solanezumab.

In the case of bapineuzumab, a compound owned by Johnson & Johnson and Pfizer with financial interests by Elan, flopped in multiple late-stage trials and was eventually shelved.

Eli Lilly's (LLY) Solanezumab also failed to meet its primary endpoint in late-stage trials, but it offered researchers some glimmer of hope in treating early stage symptoms of the disease and is being examined more closely in a longer-term international study.

Treatments: Where we're headed next

The two areas where we have significant room for improvement are diagnosing the disease and its risk factors, as well as in treating the underlying cause rather than symptoms of the disease.

In terms of diagnosis, the past month has offered a very exciting new FDA diagnostic approval, which should improve accuracy of disease risk, diagnosis, and staging of the disease. The diagnostic in question is General Electric's (GE ) (yes... GE!) Vizamyl which attaches to beta amyloid, a protein often associated with Alzheimer's disease, which can then be viewed in a 3-D PET-scan.

Vizamyl actually joins Eli Lilly's Amyvid as the only other beta amyloid-attaching drug which can be used for 3D detection purposes, however, as my Foolish colleague Patrick Morris points out, the Centers for Medicare and Medicaid Services' advisory panel has expressed skepticism about Amyvid's link between use of the brain plaque enhancing drug and overall patient health outcomes. With Vizamyl's effectiveness being established over two separate studies it looks like there could be a new sheriff in town when it comes to brain plaque diagnoses.

In terms of pipeline hopefuls, I would suggest keeping your eyes on Novartis' (NVS ) mavoglurant, which is actually being developed to treat symptoms associated with Parkinson's Disease but may wind up being a meaningful step forward in treating Alzheimer's disease.

According to a study conducted at the Yale School of Medicine and published in its journal, Neuron, researchers discovered what they believe is the missing link behind Alzheimer's disease development: a protein in cell membranes called metabotropic glutamate receptor 5 -- or in shorthand, mGluR5. Mavoglurant is a drug designed to inhibit mGluR5 and is currently being tested as a therapy for Fragile X syndrome and as a possible treatment for levodopa-induced dyskinesia associated with Parkinson's disease. Given this research, don't be surprised to see Novartis expanding their study of mavoglurant to potentially include Alzheimer's disease in the near future.

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