This Latest Study Adds 1 More Piece to the Alzheimer's Puzzle

Source: Flickr user Loren Kerns.

Alzheimer's disease is believed to be caused by a buildup of beta-amyloid plaques in the brain, which interferes with neurons and disrupts cognitive function. More than 5 million people currently suffer from Alzheimer's disease in the United States based on estimates from the Alzheimer's Association; by 2050 close to 14 million people in the U.S. will have this terrible disease.

It's a financially costly disease, with $100 billion spent on caring for Alzheimer's individuals annually and another $60 billion in indirect economic costs from absenteeism and lost productivity in the workplace. Between 2020 and 2040 the cost to treat Alzheimer's as a percentage of Medicare funding is expected to skyrocket from roughly 2% to 24%!

Source: Alzheimer's Association.

As if the idea of losing your cognitive abilities and these aforementioned costs weren't terrifying enough, the fact that the disease is incredibly difficult for researchers to fight makes it even scarier. On top of the fact that the blood-brain barrier is difficult for modern medicine to overcome, researchers aren't 100% certain how Alzheimer's develops. Don't get me wrong, researchers do have a generally good idea of what the risk factors for the disease are, such as age and family history, but there's no concrete formula that determines why one person develops Alzheimer's and another doesn't. Without knowing the catalysts of Alzheimer's, it can be difficult for pharmaceutical companies to develop a cure.

Do this and your risk of developing Alzheimer's could go way up However, last week researchers at the Northern California Institute for Research and Education in San Francisco may have discovered another piece to the puzzle.

Source: Flickr user Bill Honl.

The study, officially known as the Coronary Artery Risk Development in Young Adults Study, tracked 3,247 participants for 25 years beginning between the ages of 18 and 30, and examined the association between sedentary lifestyles and cognitive performance. What researchers discovered was that participants who watched four hours or more of television each day tended to score significantly lower in cognitive performance tests once they reached middle age. Additionally, researchers note that low levels of physical activity tended to correspond with a lower cognitive score. Researchers came to these conclusions after participants completed three questionnaires over the 25-year period.

These findings could prove to be a bit of a double-edged sword. On one hand, young adults and children have more electronic entertainment options than ever (the Internet, laptops, video gaming systems, smartphones, tablets, and so on), which could bode poorly for the future if the findings from the aforementioned study are correct. On the other hand, the study findings would seem to suggest that it's not too late for Americans to reverse or slow the effects of Alzheimer's or dementia by living an active lifestyle.

Could relief be on the way? If there is a bit of a ray of sunshine to this otherwise terrible disease, it's that two drug hopefuls could be hitting pharmacy shelves within the next two or three years that have a genuine opportunity to improve Alzheimer's patients' quality of life.

The first company, Axovant Sciences , which just went public in June, is developing RVT-101 for patients with mild-to-moderate Alzheimer's. RVT-101 was jettisoned by GlaxoSmithKlinein December for just $5 million, but less than two weeks ago Axovant showed that there could be significant value in RVT-101 as an adjuvant therapy with Aricept.

According to the data from Axovant's 684-person phase 2b study, patients receiving Aricept and 35 mg of RVT-101 demonstrated statistically significant improvements in cognition and function at the 12-, 24-, 36-, and 48-week marks, as measured by the Alzheimer's disease Assessment Scale, compared to the Aricept monotherapy arm. Furthermore, the magnitude of the cognitive and functional benefits tended to improve as time passed. The combination was also well-tolerated by patients. Axovant anticipates starting a phase 3 trial by the fourth quarter of this year and could bring RVT-101 to pharmacy shelves by as early as 2017.

Based on estimates from a number of Wall Street analysts, RVT-101 could have peak annual sales potential in the $2 billion to $3.5 billion range if it's successful in phase 3 studies. Keep in mind the failure rate of experimental Alzheimer's drugs is very high.

Source: GlaxoSmithKline.

The other experimental therapeutic worth monitoring is aducanumab from Biogen . Perhaps no drug wowed Wall Street more in 2015 than aducanumab, with its full data release in March.

In Biogen's 166-patient phase 1b study involving aducanumab there was a pronounced decrease of beta-amyloid plaques that resulted in a statistically significant improvement in mental decline. The 30-point mental acuity test, which helped establish the performance of the aducanumab arm versus the placebo, showed a 3.14 point decline in the placebo group compared to just a 0.75 point and 0.58 point decline for the groups receiving 3 mg and 10 mg doses of aducanumab.

A similarly strong result was established with the 10 mg dose of aducanumab in the 18-point Clinical Dementia Rating. The placebo group showed a 2.14 point decline, while the 10 mg aducanumab group sported a decline of only 0.59 points. It should be noted that the 3 mg aducanumab dose didn't meet statistical significance in the Clinical Dementia Rating.

These results were so impressive that Biogen completely skipped phase 2 studies and jumped right into a large-scale phase 3 trial. It's possible we could have data as early as next year, with aducanumab hitting pharmacy shelves by as early as 2017 if everything goes as planned. Per Wall Street analysts, aducanumab has the potential for as much as $10 billion in peak annual sales.

Long story short, Alzheimer's remains an elusive and terrifying disease, but researchers are throwing the metaphorical sink at this disease in the hope of sometime soon finding a cure. Even if RVT-101 and aducanumab aren't end-all cures, they do represent a marked step in the right direction if successful. I'm personally cheering both experimental therapies on and hoping for the best, but I also understand that the odds are very much against researchers succeeding.

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