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While we Fools tend to champion owning companies that are high-quality, stable, and spit out gobs of cash flow, we realize there is nothing wrong with speculating every now and then on a stock that offers huge upside.

We reached out to our team of Motley Fool healthcare contributors and asked them to share a biotech stock that they think could realistically double within the next year. Read below to see which stocks they singled out.

Brian Feroldi: One company I think could double in value in 2016 is Keryx Biopharmaceuticals (NASDAQ:KERX), a drug developer with a focus on renal disease. The company's stock has been kicked in the teeth ever since its first and only drug, Auryxia, become available for sale. Auryxia got off to a slower than expected start, causing the company's doubters to short it like crazy, and its stock cratered. Keryx Biopharmaceuticals' stock dropped more than 64% in 2015 alone, and it's down even more than that from its 2014 highs.  

So, why do I think the company's stock could double in 2016? Three reasons. First off Keryx Biopharmaceuticals recently received European approval to market Auryxia, which will sell under the brand name Fexeric. That approval more than doubles the drug's addressable market, and the company is set to announce its go-to market strategy for the region any day now.

Phase 3 data on Auryxia in patients who are in pre-dialysis is expected out sometime in the second quarter. If that data looks good, then the company could submit for a label expansion claim soon after, which could also significantly expand the drug's addressable market. Finally, the company just got a big cash infusion from famed investor Seth Klarman's Baupost Group, which is now the company's largest shareholder. This gives the company all the capital to build out its sales force so it can market Auryxia successfully.

Success is still far from certain, and this is still a very high-risk name, but with several positive catalysts on the horizon, it wouldn't take much good news for this beaten down stock to shoot higher. 

Keith Speights: A little over three years ago, I stepped out on a limb and predicted that investors could possibly double their money by buying Dynavax Technologies Corporation (NASDAQ:DVAX). Within a couple of days, an FDA advisory panel voted against recommending the biotech's hepatitis B vaccine for approval. Shares tanked.

While I was horribly wrong about Dynavax then, the future for the company appears to be quite bright now. Preliminary results from a phase 3 clinical study of Heplisav-B were just announced. Those results were very good with both co-primary endpoints met. The news sent Dynavax shares soaring.

If Heplisav-B ultimately wins regulatory approval, the vaccine seems to be a shoo-in for commercial success. The current leading hep-B vaccine, Engerix-B, requires dosing for six months. Heplisav-B offers more protection against the virus with fewer doses in just one month. I think this time around, Dynavax is destined for good news -- and its stock just might have a shot at that double I predicted several years ago.

Sean Williams: If you want a make-or-break biotech stock that could be a darling or a goat in 2016, look no further than clinical-stage drug developer Sarepta Therapeutics (NASDAQ:SRPT).

Sarepta Therapeutics' possible claim to fame is its lead drug eteplirsen, which is focused on the treatment of Duchenne muscular dystrophy, a disease in children, teens, and young adults characterized by an absence of the protein dystrophin, which is essential for keeping muscle cells intact. There are numerous variations of DMD; eteplirsen is specifically focused on exon 51, which encompasses one in eight cases.

In clinical studies, eteplirsen has been a veritable star. At the 48-week mark in a midstage study, eteplirsen actually led to an improvement of six meters in the six-minute walk test (6MWT) from baseline for patients on the drug, compared to a nearly 60-meter regression for the placebo cohort. In its phase 2b extension study, eteplirsen has continued to deliver a 65-meter statistical advantage in the 6MWT over the placebo, even with 6MWT degradation in baseline from both groups after more than three years (168 weeks). Sarepta's management strongly believes that starting this drug subsequent to diagnosis could extend its benefits.

Eteplirsen is set to go before the Food and Drug Administration's panel this month, and it has a PDUFA decision date of Feb. 26, 2016. If approved, Sarepta would be able to place an orphan drug price tag on eteplirsen and could generate substantial revenue out of the gate. At its peak, eteplirsen could generate anywhere from $600 million to $1 billion in annual sales. More importantly, though, it would validate Sarepta's exon-skipping platform, which would mean its research into more than a half-dozen other exon-skipping DMD drugs may also be successful. If that's the case, Sarepta could treat about half of all DMD patients by the end of the decade. 

If eteplirsen is approved by the FDA, which is no guarantee, it could be on track to double in 2016. Of course, understand that a rejection of eteplirsen would throw Sarepta's entire exon-skipping drug development platform into question. This is a high-risk, high-reward opportunity for only the most risk-tolerant investors in 2016.