I’ve been tracking this vaccine maker for a few quarters now after writing about the company a few months ago. Shares initially surged above $2 at the start of 2014 but have drifted back down to levels seen last November.

Part of the blame goes to a decision last month to withdraw an existing application for European approval, which means that any launch in Europe for virus-fighter Hepislav won’t take place until 2017, two years later than previously thought. (Good thing that the company shored up the balance sheet in 2013, as Dynavax now has $189 million in cash.)

The nearest-term catalyst for Hepislav is the imminent enrollment in safety trials here in the U.S. The trial could help strengthen this drug’s prospects in Europe as well, as European regulators delayed its approval process due to a too-small sample size of safety data thus far.

Beyond Hepislav, which is targeting hepatitis B, Dynanax also has a promising drug, known as AZD1419, to treat asthma and chronic obstructive pulmonary disorder (COPD). AstraZeneca (NYSE: AZN) is helping to test the drug, and the two firms have a multi-tiered royalty and milestone agreement in place.

Though shares languish below $2, analyst at MLV see more than 150% upside to their $5 price targets, solely on the basis of Hepislav’s projected revenue streams. Any value generated by AZD1419 would be pure upside from that price target.

Though biotech firms are focused on drugs that may face large market niches, small medical device makers have similar hopes and dreams, and can be seen as the same kind of high-risk/high-reward situations as biotechs are. (I profiled this company for our sister site ProfitableTrading.com at the end last year.)

Though this company’s market potential remains intact, the time-frame has changed since my December review. Just a few days ago, Enteromedics announced that the FDA will review its VBLOC technology on June 17, roughly a quarter later than previously anticipated. As I noted back in December, FDA approval (and an eventual well-executed sales launch) could send this stock up more than 200% to Northland Securities’ $7 target price.

If you would rather not wait several years for a biotech stock to fulfill its potential, then Chelsea Therapeutics (Nasdaq: CHTP) may represent a more compelling near-term option.

The company recently received approval for Northera, a drug which treats NOH (neurogenic orthostatic hypotension). Though Chelsea aims to launch the drug later this year, companies like this often end up seeking a buyer that already has an existing sales force to peddle a new drug. The company has already stated that it is considering “strategic alternatives,” which is a code for putting out investment banking feelers. On a stand-alone or a buyout basis, JMP Securities sees shares rising more than 125% to $12.

I looked at this clinical-stage drug developer nearly a year ago and since then, shares swooned and have returned right back to levels seen a year ago.The erratic price movement can be attributed to a weakening balance sheet that was eventually rescued by a 2013 capital raise. (This article on Seeking Alpha provides a good update on the company’s status.)

The good news: As that article notes, a pair of updates regarding clinical trials could help boost confidence that Synergy’s plecanitide drug will prove to be more popular than rival Ironwood Pharma’s (Nasdaq: IRWD) Linzness. Though approval for Synergy isn’t guaranteed, the data thus far have been so robust that approval looks likely.

Why would this stock have at least 100% upside? Because Synergy is valued at $550 million, while Ironwood is valued at $1.64 billion. If and when Synergy’s Plecanatide is approved, its market value may end up being higher, thanks to comparatively stronger efficacy and tolerability for its drug.