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Biotech investors are constantly faced with a dilemma. Buy the safer names, which come with lower risk but whose sheer size prevents them from producing multi-bagger returns? Or look to the small-caps, which certainly hold the ability to multiply an investment many times over, but often come with enormous risks?

To find a company that offers the best of both worlds it sometimes makes sense to look at the mid-cap companies, as they tend to occupy that goldilocks sweet spot -- not too big and not too risky. We asked our team of Motley Fool contributors to share biotech investment ideas that have market caps between $2 and $10 billion that have them excited. Read below to see if you agree with their suggestions.

George BudwellSeattle Genetics (SGEN), a leader in the field of antibody drug conjugates, or ADCs, is a mid-cap biotech stock that has caught my eye of late for a couple of reasons. 

First up, the company's flagship drug, Adcetris, has been generating double digit sales growth since its launch, and is presently on track to break $210 million in sales this year. 

While that's not enough to transform Seattle Genetics into a cash flow positive operation at present due to the company's robust clinical program, Adcetris did recently garner its third regulatory approval in the U.S. as a treatment for non-Hodgkin lymphoma in post-stem cell transplant patients. As a result, Seattle Genetics' quarterly net losses should start to shrink in a noteworthy fashion in 2016, and the company may even become cash flow positive as soon as 2017.

Secondly, Seattle just completed a hefty $480 million stock offering that helped to shore up its balance sheet for the long haul. If all goes according to plan, this should be the company's last major financing deal -- this latest one should extend Seattle's cash runway by an additional two and half years based on the drugmaker's current burn rate.  

Given the steady progress of its lead product and improving financial situation, I think all systems are now a go for Seattle Genetics, making now a good time to think about picking up some shares in this mid-cap biotech.

Todd Campbell:  One of my favorite mid-cap companies is Insys Therapeutics (INSY), a profitable biotech that markets Subsys, a fast-growing opioid pain reliever for breakthrough pain in cancer patients.

Since winning the FDA nod in 2012, Subsys has captured an increasingly large share of its addressable patient population thanks to its under-the-tongue spray formulation, which allows it to work more quickly and have its dosage adjusted more easily. Last quarter, sales of Subsys hit $76.7 million, up 40% year-over-year.

Subsys, however, is only one of the reasons why I like Insys. The company has also recently submitted an oral formulation of Marinol to FDA regulators for approval; if it gets the green light, then Insys could win away a considerable share of a market that Insys values at north of $150 million annually.

Additionally, Insys is researching whether or not it can apply its spray technology to other off-patent therapies, including the widely used pain-killer buprenorphine, and studying the potential to treat rare forms of epilepsy with the marijuana chemical cannabidiol, too.

Subys is kicking off plenty of cash, the company is debt-free, and despite increased spending on R&D, the cash on its balance sheet is growing. For all those reasons, I think Insys Therapeutics may be a good bet for risk tolerant investors looking for a mid-cap growth stock.

Brian Feroldi: One mid-cap that I've had my eye on for a while is JAZZ Pharmaceuticals PLC (JAZZ -2.56%), maker of drugs that treat patients in the sleep and hematology/oncology markets. This stock has been an amazing winner over the past 5 years -- it's up more then 13-fold over that time, leaving investors who got in early with huge profits.

Jazz has been a stellar performer thanks in large part to Xyrem, the company's flagship narcolepsy medication. Sales of Xyrem grew 37% in 2014 to more than $770 million, and only about 12,250 patients currently use the medicine in the U.S., which is a tiny fraction of the 160,000 believed to have narcolepsy -- meaning there's plenty of room for strong growth ahead.

Beyond Xyrem, Jazz has a nice pipeline of opportunities that should extend its leadership position in the sleep market, as well as some new medications tied to the hematology and oncology markets that, if approved, could power growth for the company in the years to come.

Analysts see this company growing its profits by more than 19% annually over the next 5 years, which is impressive for a stock that is only trading around 13 times estimated 2016 earnings. For investors who are looking to make an investment in biotech and don't want to take on a ton of risk, I think JAZZ is a good choice.