The short interest data are out for the January 15 settlement date. Biotech companies are considered a riskier group of stocks, with big upside and big downside. FDA rulings can make or break them. A single failed clinical trial can mean disaster for a stock. 24/7 Wall St. has reviewed the top biotech companies, without focusing on speculative companies.

The January 15 short interest data have been compared with the December 31 figures, and for the majority of the selected stocks, short interest is down.

Amgen Inc. (NASDAQ: AMGN) saw its short interest decrease to 7.7 million shares, with 2.1 days to cover. The previous short interest reading was 8 million with 2.1 days to cover. The short interest for Amgen has taken a dip for these past three settlement dates, recording the lowest levels on the year. Shares closed Tuesday at $158.89, in a 52-week trading range of $108.20 to $173.14.

Biogen Idec Inc. (NASDAQ: BIIB) saw its short interest rise to 3.3 million, with 1.6 days to cover, from the previous level of 2.9 million shares with 1.6 days to cover. The company is coming off its lowest short interest readings in November and seemingly returning to its recent historical levels. Shares closed Tuesday at $357.89, within a 52-week trading range of $272.02 to $366.17.

ALSO READ: Short Sellers Pounce on Major Oil and Gas Stocks

Celgene Corp. (NASDAQ: CELG) saw a short interest increase for this settlement date, up to 12.7 million shares, with 2.1 days to cover. The level for the previous settlement date was 10 million, with 2.2 days to cover. Since March, Celgene has recorded its two lowest relative readings in the past two settlement dates. This potentially signals some optimism from investors. Shares of Celgene closed Tuesday at $122.36, in a 52-week trading range of $66.85 to $124.60.

Gilead Sciences Inc. (NASDAQ: GILD) saw its short interest increase to 55.3 million, with 3.1 days to cover, from 52.9 million with 2.0 days to cover. Investors seem to have backed off shorting this stock in September, when shares were poised to hit 52-week highs. Shares closed Tuesday at $105.03, in a 52-week trading range of $63.50 to $116.83.

Mannkind Corp. (NASDAQ: MNKD) saw its short interest rise to 76.9 million shares, with 17.2 days to cover. The previous reading was 75.7 million with 18.1 days to cover. Short interest for Mannkind appears to have steadily backed off, if only a little, from its 52-week highs following the market sell-off in October. Shares closed Tuesday at $6.36, in a 52-week trading range of $3.80 to $11.48.

ALSO READ: Short Sellers Run for Cover in Semiconductor Stocks

Alexion Pharmaceuticals Inc. (NASDAQ: ALXN) short interest increased to 3.2 million shares, with 2.2 days to cover, up from the previous level of 2.9 million with 2.2 days to cover. The past three readings are among the lowest short interest for the year. Shares closed Tuesday at $180.36, in a 52-week trading range of $129.80 to $203.30.

Thank you for reading! Have some feedback for us?
Contact the 24/7 Wall St. editorial team.