For the period that ended July 31, short sellers cut their position in Biogen Idec Inc. (NASDAQ: BIIB) 3.9% to 2.4 million. The short interest in Celgene Corp. (NASDAQ: CELG) dropped 11.8% to 6.3 million. Shares short in Gilead Sciences Inc. (NASDAQ: GILD) declined 1.9% to 18.0 million. Shares short in Onyx Pharmaceuticals Inc. (NASDAQ: ONXX) fell 4.8% to 5.9 million. The short interest in VIVUS Inc. (NASDAQ: VVUS) dropped 8.9% to 13.8 million.
However, the short interest in Dendreon Corp. (NASDAQ: DNDN) was higher by 7.0% to 40.8 million, its largest short interest in months. And the short interest in Regeneron Pharmaceuticals Inc. (NASDAQ: REGN) rose 7.2% to 4.9 million. Shares of Dendreon recently plunged after the company released disappointing second-quarter earnings results and announced a restructuring plan that will trim 600 jobs, or 41% of the company’s workforce. Furthermore, in July the Food and Drug Administration rejected expanded use of Regeneron’s drug for gout, but this month the FDA approved a colon cancer drug Regeneron developed with Sanofi (NYSE: SNY).
Also the short interest in Amgen Inc. (NASDAQ: AMGN) rose 3.9% to 12.5 million, and shares short in Illumina Inc. (NASDAQ: ILMN) climbed 2.0% to 21.4 million.
Dendreon is up about 3.3% in early trading to $4.65, in a 52-week range of $4.17 to $17.04. Regeneron is up 0.3% to $138.40 in a 52-week range of $47.11 to $145.04.