Looking at how Acadia Pharmaceuticals (NASDAQ:ACAD) lost almost half its value yesterday, you'd think that the company lost half of the drugs in its clinical pipeline.

Oh wait, it did lose half the clinical-stage drugs in its pipeline.

The development-stage drugmaker announced yesterday that its ACP-104 failed to show an effect treating schizophrenia patients in its phase 2b trial. In a refreshing move, unlike many companies without drugs on the market, Acadia didn't candy-coat the results and talk about how it'll analyze the data and try to test it against another disease. Besides publishing the negative results, it sounds like Acadia is done with ACP-104 and on to bigger and better things.

Essentially, that leaves Acadia with another antipsychotic, pimavanserin, which was previously referred to as ACP-103. It also has a deal with Allergan (NYSE:AGN) to develop drugs to treat pain caused by neurological damage. Acadia could get milestone and royalty payments if Allergan successfully develops drugs from the partnership.

Pimavanserin is in two phase 3 trials, testing its ability to treat psychosis caused by the progression of Parkinson's disease. These trials should start to produce data next year. It's also being tested as a treatment for insomnia and, in combination with Johnson & Johnson's (NYSE:JNJ) Risperdal, as a treatment for schizophrenia. The latter two indications seem to be on hold until Acadia can find a partner for pimavanserin.

Speaking of partners, Acadia has been saying that it would like to find a partner for pimavanserin since the phase 2 schizophrenia data came out in March of last year. Given the lack of a partner 15 months later, it seems like big pharma isn't all that interested in the drug -- and the lack of a backup drug, now that ACP-104 is out of the picture, would seem to work against Acadia at the bargaining table. Fortunately, the company doesn't have to find a partner for the drug tomorrow; Acadia says that it has enough money in the bank to make it through 2009. Even so, I'm sure investors would rather see one sooner rather than later.

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