Crunch Time at Teva

He expects Agilect to win FDA approval as a single early-stage medication and as part of combination later-stage treatments.

Watson views Agilect as a next-generation drug, but he says Zelapar is basically a reformulation of selegiline. Valeant is seeking FDA approval for Zelapar as a combination treatment with levodopa.

Watson has buy ratings on Teva and Valeant. He doesn't own shares in either company, but his firm says it plans to receive or seek investment-banking compensation from both companies in the next three months.

Each drug will have modest U.S. sales due to "significant generic competition," says Andrew McDonald of ThinkEquity Partners. "It's hard to imagine more than $50 million a year in peak sales."

McDonald notes that Valeant inherited Zelapar when it acquired the U.S. division of another company last year. Valeant has had to conduct additional tests on the drug. He has a sell rating on Valeant. He doesn't own shares, and his firm doesn't have an investment-banking relationship.

Sagient Research predicts that Agilect's peak annual revenue in the U.S. could be $201 million ($500 million worldwide) and that Zelapar's peak U.S. sales could be $163 million ($412 million worldwide).

Many Choices

If these drugs reach the market, they'll have plenty of competition.

Dopamine agonists, which stimulate the dopamine receptors in the brain, have been available for about 30 years. Brand names include Mirapex from Boehringer Ingleheim and Pfizer (PFE), and Requip from GlaxoSmithKline (GSK).

Another class is COMT inhibitors, which block an enzyme from breaking down levodopa and dopamine. Novartis (NVS) offers two COMT inhibitors -- Comtan and Stalevo, which combines Comtan with levodopa/carbidopa.

Several companies are conducting clinical trials of adenosine A2a receptors, compounds that try to modulate side effects experienced by patients who now take the strongest drugs. Major players include Schering-Plough (SGP), Biogen Idec (BIIB) and Japan's Kyowa Hakko Kogyo..

And there's more. By Sagient Research's count, there are eight other experimental drugs for Parkinson's in late-stage clinical trials or midstage clinical trials. Unfortunately, none looks it can slow or stop the disease.

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