As the heat and humidity begin to rise, consider these biotech stocks to make your portfolio sizzle this summer.

Since I first profiled Advanced Life Sciences (NASDAQ:ADLS) last week, shares have drifted down more than 10% to a Tuesday close just below $3 per share. June will be a pivotal month for the company, because it's expected to release what should be positive results from two phase 3 trials for its once-daily ketolide antibiotic called cethromycin in the treatment of community acquired pneumonia (CAP). Near-term catalysts include the cethromycin data in June and the possible signing of a co-promotional partnership deal for the drug later this year.

Depomed (NASDAQ:DEPO) is a micro-cap drug-delivery specialist whose polymer-based AcuForm delivery technology has the potential to reduce the dosing frequency for a variety of orally administered drugs. The company already has two products approved for marketing -- Glumetza (metformin) for diabetes and Proquin (ciprofloxacin) extended release for urinary-tract infections.

As a near-term catalyst, in the new few months the company is expected to report phase 3 top line results for its Gabapentin GR for nerve pain arising from shingles. Gabapentin GR has a much larger sales potential than both of the currently marketed products combined, since it is a widely used drug (including the treatment of many off-label conditions) that is currently taken three to four times daily. The company's version of gabapentin will only be dosed one to two times daily, which should be enough of an advantage to warrant premium pricing and gain market share in an off-patent environment that is currently dominated by generic forms of the drug. I believe shares of Depomed are attractively valued at present, and represent a buy at current levels in anticipation of positive phase 3 results and potential licensing deals for both existing products and drug candidates in the company's pipeline.

Theravance (NASDAQ:THRX) has an interesting deadline approaching in July, whereby strategic partner GlaxoSmithKline (NYSE:GSK) has a call option to acquire up to 59.4% of total shares outstanding for a price of $54.25. Glaxo already owns a 15.6% stake in Theravance that consists of all of the company's class A common stock. Alternatively, Theravance's shareholders have the right to cause Glaxo to acquire up to half of their outstanding common stock in August at $19.375 per share, with a maximum obligation of $525 million. If neither the call nor put options are exercised, public shareholders would retain 100% of their existing shares.

Beyond the potential call option exercise by Glaxo, Theravance has a deep pipeline of products with huge sales potential. Telavancin is the company's most advanced drug candidate, with an expected FDA approval in early October. Telavancin is a powerful IV-administered antibiotic which is reserved for serious infections that are resistant to other antibiotics. The company has partnered with Canadian-based Astellas for the drug and is set to receive an additional $95 million in milestone payments, along with a tiered royalty rate based on net sales that ranges from the high teens to high 20s on a percentage basis. Astellas will pay all commercialization costs for telavancin. The drug's unique, dual mode of action differentiates it from currently used antibiotics, giving the drug a reasonable chance at reaching the highest tier for royalties on annual sales exceeding $500 million.

Astellas also has an option to license another antibiotic in Theravance's pipeline that is a combination (heterodimer) of two distinct antibiotic modes of action in one molecule that is also designed for serious infections resistant to standard treatments. Another potential big seller in the pipeline is TD-5108, a once-daily drug designed to treat gastrointestinal motility disorders such as chronic constipation, constipation-predominant irritable bowel syndrome, severe heartburn, and related conditions. This category is a billion-dollar opportunity for Theravance with a current void caused by the March 2007 withdrawal of Zelnorm from the market and the 2000 suspension of Propulsid, both because of heart concerns. Finally, Theravance has an additional Beyond Advair collaboration with Glaxo, with the goal of developing once-daily products for respiratory conditions such as asthma and COPD that improve upon Glaxo's $4 billion Advair franchise. Look for clinical trial data on most of the aforementioned pipeline drugs during the latter half of this year.

Since I first profiled ThermoGenesis (NASDAQ:KOOL) at the end of April, shares have dropped about 10%. Last week, the company announced that it received an approvable letter from the FDA for its CryoSeal Fibrin Sealant System. The company intends to address the issues raised by the FDA, including submission of final labeling, an operator manual, and related documents. ThermoGenesis believes that all outstanding issues will be submitted in time for the FDA to complete its approval process before the end of the company's fiscal year on June 30. In addition, the company could hear back from the FDA as early as the second week in August (six months from the application submission) on its 510(k) pre-market notification application that is requesting regulatory clearance for its AutoXpress System for cord blood processing and is currently being marketed in a partnership with GE Healthcare.

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Fool contributor Mike Havrilla, R.Ph., B.S., Pharm.D., is a Rite Aid pharmacist who lives, writes, works, and enjoys running on the streets and trails in the small Pennsylvania town of Portage. He invites your comments and feedback. Mike does not have a position in any company mentioned in this article. GlaxoSmithKline is an Income Investor recommendation. The Fool has a disclosure policy.