Yesterday development-stage drugmaker Vanda Pharmaceuticals (NASDAQ:VNDA) guided investors on what to expect for the rest of the year in conjunction with its second-quarter financial results.

Vanda's lead drug is the antipsychotic compound iloperidone, which completed testing as a treatment for schizophrenia last year. On the conference call yesterday, Vanda reiterated its guidance for the iloperidone New Drug Application to be completed by the end of the year and for an FDA regulatory decision to likely come ten months or so later in late 2008.

I wrote about iloperidone and what some of the drug's benefits and drawbacks were earlier this week. Vanda plans on presenting more safety and efficacy data on the drug at two medical conferences in October and December. I don't think that the efficacy of iloperidone is in doubt, but investors should pay close attention to what Vanda has to say on the drug's safety, in particular its effects on the heart.  

Vanda's other two compounds are the insomnia treatment VEC-162, which it licensed from Bristol-Myers Squibb (NYSE:BMY); and the interesting wakefulness-promoting drug VSF-173. VEC-162 will enter another round of phase 3 testing in the fourth quarter. Results from a phase 2 study of VSF-173 are expected to be released by the end of 2007 as well.

What makes VSF-173 very intriguing is that there is only one other currently approved drug, Provigil by Cephalon (NASDAQ:CEPH), that serves this market; and that interpreting efficacy results from wakefulness studies is fairly straightforward, which investors and the FDA always like. Provigil is on its way to becoming a billion-dollar blockbuster drug, so there would be a big market for VSF-173 if it can get to the market with a suitable safety and efficacy profile.

During the conference call Vanda gave no new updates on its progress with finding partners for any of its compounds despite analyst grilling on the subject in the Q&A session. Vanda still has enough cash on hand to last it through the middle of 2008, so it is in no immediate need of having to make a deal to avoid a dilutive financing.

The next few months will provide some interesting times for Vanda with the upcoming iloperidone scientific presentations and VSF-173 study results. Investors should be prepared for a volatile road ahead as Vanda's share price reacts to all the news.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool has a disclosure policy.