BOSTON ( TheStreet) -- Investing in biotech stocks is tricky. Biotechs are usually unprofitable and burn through cash, appearing destined for shareholder dilution or bankruptcy court. Yet, those that do succeed deliver obscene returns. Dendreon ( DNDN), which developed the Provenge prostate-cancer drug, has surged, on average, 68% a year since 2007.Here are 10 of the highest-rated biotech stocks. They're exceptionally risky, but predicted by analysts to double, triple, quadruple or even quintuple in the next 12 months. Below, they are ordered by projected return, from big to biggest. Investors should investigate each company and its drug candidates. 10. NeurogesX ( NGSX) develops novel pain-management therapies. NeurogesX's second-quarter loss widened 88% to $10 million, or 58 cents a share, as revenue turned positive. The operating margin remained negative. NeurogesX has $68 million of cash and $40 million of debt, equal to a quick ratio of 4.9. Its stock trades at a sales multiple of 21 and a cash flow multiple of 7.3, 79% and 60% discounts to peer averages. All five of the analysts covering NeurogesX rate its stock "buy." A median price target of $14 implies that the stock will rise 96%. Bullish Scenario: Roth Capital Partners predicts that NeurogesX's stock will gain 123% to $16.