As a speculation on an Alzheimer's drug, Michael Shulman owns Prana (NASDAQ: PRAN), but cautions that it is the riskiest stock on his Changewave Biotech Investor buy list.

"The company's Alzheimer's disease drug drug, called PBT-2, is in Phase II trials in Sweden and aims at limiting the interaction between naturally occurring metals in the body (specifically in the area of the brain) and beta amyloid proteins that are at the heart of the plaques thought to be the cause of Alzheimer's disease.

"Prana has its place in our highly speculative portfolio because most other science aimed at limiting the creation of plaques has failed big time by taking a totally wrong approach discredited during the past three years.

"Prana is indeed a long shot. It's one of those biotechs we sometimes love and sometimes hate. Its current trials will be completed in December and if they show efficacy the stock is worth $7-$10.

"If and when PRAN finds a partner to fund phase III trials, the stock is maybe worth $12-$20. Of course, there is the downside possibility that the drug fails and the stock is then worth 50 cents.

"The current price is $3-plus, and it's worth purchasing if you have some Vegas money that's burning a hole in your pocket -- please, not the mortgage money or any other funds you'd miss."