Tech has been questionable, oil's been volatile. Despite this, the S&P 500 and Dow Jones Industrial Average have done a good job holding up over the past few weeks. But one industry that continues to do well? Biotech.

The iShares Nasdaq Biotechnology Index ETF (IBB) is up 5.4% over the past month, 7.1% over the past three months and 16.8% on the year. But for those who are looking for more specific picks, Jefferies is here to help.

Analysts were out with a slew of upgrades, notably on some big names, too. Jefferies initiated Celgene (CELG) with a buy rating, while assigning a hold rating to Gilead Sciences (GILD) and Biogen (BIIB) . The analyst sees Celgene climbing to $160, Gilead to $80 and Biogen to $310.

In other words, they see more than 21% upside in Celgene, 15% upside in Gilead and 13% in Biogen. Even for a pair of hold ratings, double-digit upside would be pretty attractive.

But Jefferies didn't stop there. Analysts also initiated new coverage on Vertex Pharmaceuticals (VRTX) , assigning it a buy rating and $155 price target. They also started Intercept Pharma (ICPT) with a buy rating and $275 price target. Their respective price targets imply 21% and a massive 127% in potential upside.

Most of these five stocks were not showing much, if any, movement in Tuesday's morning trading session. However, shares of ICPT are up almost 4%, which should come as little surprise when an analyst calls for a more than doubling to its stock price.

However, one should note that Intercept once traded north of $275 as recently as July 2015.

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This article is commentary by an independent contributor. At the time of publication, the author had no positions in the stocks mentioned.

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