Now that baseball season is in full swing with the unofficial, post-Memorial Day start of summer, I am offering biotech investors a triple play of their own for June: Panacos, Acadia, and Encysive.

As stated in an article earlier this month, Panacos Pharmaceuticals (NASDAQ:PANC) is conducting a phase 2b trial with liquid HIV treatment candidate bevirimat, the first of a new class of oral HIV drugs. Results are expected at the end of June. Data on trials using increasing doses will be reported in upcoming quarters.

Investors will want to tune into a presentation by Panacos' CEO this Wednesday at the Bank of America Health Care Conference for more information. With a market cap just over $200 million, Panacos is an attractive investment, if you believe as I do that the company is poised to resolve its oral formulation issues, which caused the stock to tank last year due to the time and money costs of a delay in clinical development.

Shares of Acadia Pharmaceuticals (NASDAQ:ACAD) skyrocketed in mid-March when the company reported positive top-line results from a phase 2 schizophrenia co-therapy trial combining its pimavanserin (formerly ACP-103) with either Risperdal or Haldol. Co-therapy advantages over the antipsychotics used alone included enhanced efficacy and an improved side-effect profile.

The company is now in the final stages of preparing to initiate its first pivotal trial in a phase 3 program with pimavanserin for Parkinson's disease psychosis, and a phase 2b trial with ACP-104 for schizophrenia. Acadia also completed a public offering last month that raised net proceeds of $96.1 million through the sale of 6.6 million shares of its common stock. Investors will have plenty of opportunities to stay updated on Acadia, as the company will be presenting at three upcoming investor conferences over the next month.

In the near term, Acadia appears poised to maintain its upward momentum, as most analysts are busy upgrading their price targets and ratings on the stock in anticipation of potentially lucrative licensing deals for both lead drugs, primavanserin and ACP-104. Obvious partners would be Risperdal's manufacturer, Johnson & Johnson (NYSE:JNJ), along with mental health drug giant Eli Lilly (NYSE:LLY). However, some analysts are skeptical, pointing out that phase 3 trials will present a more formidable tests. 

Also, since ACP-104 is the major active metabolite of the existing antipsychotic clozapine, there are concerns over the potential for the serious side effects that have restricted clozapine to a last-line treatment. If Acadia's ACP-104 can jump this important safety hurdle, however, it has potential blockbuster status as it possesses a novel, additional mode of action in the brain.

Motley Fool Rule Breakers pick Encysive Pharmaceuticals (NASDAQ:ENCY) has a key date of June 15 for the FDA to decide on the company's drug Thelin in the treatment of pulmonary arterial hypertension (PAH). PAH is high blood pressure that is specific to arteries in the lungs, which causes undue strain on the right side of the heart. While my feeling is that Thelin will likely be approved, the labeling and potential competition from Gilead's (NASDAQ:GILD) ambrisentan (with approval likely for PAH three days later) will be the major challenges for Encysive.

Thelin also faces concerns over the drug's interactions with the widely used (among PAH patients) blood thinner warfarin. There also are concerns over liver enzyme elevation that could dampen the enthusiasm of physicians and the sales potential of the drug versus ambrisentan. As mentioned in an article earlier this month, Thelin is also expected to receive Canadian approval by the end of June, and negotiations with France's and Spain's health care systems over the price of the drug are expected to be completed later this year. Reimbursement is already complete in Germany and the U.K.

Even with the company's current market cap of just $260 million, I consider an investment in Encysive speculative in anticipation of likely upcoming approvals in the U.S. and Canada, in addition to increased European sales where the drug was approved for marketing last year. While Thelin may not have blockbuster sales potential, Encysive can still carve out a profitable niche for the drug given the low valuation being placed on the company by the market. At the very least, FDA approval would finally give Encysive shareholders a sigh of relief after long delays and previous disappointments for Thelin, while providing the company with a chance to develop a profitable business model. This, of course, assumes the FDA approves Thelin next month and that is far from certain as the drug has been turned down twice now.

So take a good look, assess your tolerance for risk and decide if this game's for you.

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Fool contributor Mike Havrilla, R.Ph., B.S., Pharm.D., is a full-time  pharmacist who aspires to be a biotech analyst. He invites your comments and feedback. Mike does not have a position in any company mentioned in this article. The Fool has a disclosure policy. Bank of America, Johnson and Johnson, and Eli Lilly are Income Investor recommendations. Panacos is a Rule Breakers selection.