Biogen And Gilead Sciences Buck Biotech Short Interest Trend

• Short interest in many of the leading biotech stocks shrank in the most recent period.
• Two stocks in particular stood out among the few that bucked the trend in those two weeks.
• Shares of both of these stocks rose sharply during the two-week period.

Short sellers shied away from many of the leading biotechnology stocks as the markets reached for year-to-date highs in late May. However, a few stocks in the industry bucked that trend between the May 13 and May 31 settlement dates.

Biogen Inc BIIB and Gilead Sciences, Inc. GILD in particular saw sharp increases in the number of their shares short, in a period in which the former got an FDA nod for a multiple sclerosis drug, and the latter named a new chief operating officer.

Others that saw modest rises in short interest include Incyte and Juno Therapeutics, while the number of shares short in Celgene, Opko Health and Vertex Pharmaceuticals hardly changed at all between the settlement dates.

The final weeks of the month brought shrinking numbers of shares short at Acadia Pharmaceuticals, Alexion Pharmaceuticals, Anacor Pharmaceuticals, Amgen, Baxalta, BioMarin Pharmaceutical, Illumina, Intrexon, Medivation and Seattle Genetics.

Below is a quick look at how Biogen and Gilead Sciences have fared recently and what analysts expect from them.

Related Link: Downside Ahead For Biotech Stocks?

Biogen

This company focused on therapies for the treatment of neurodegenerative diseases, hematologic conditions and autoimmune disorders saw its short interest rise more than 8 percent to more than 2.43 million shares, or 1.1 percent of float, in the final weeks of the month. At the most recent average daily volume, it would take less than two days to cover all short positions.

Biogen also said its Alzheimer's treatment was accepted for review in Europe in the period. Short sellers watched the shares rise more than 10 percent during the two-week short interest period, compared to a less than 5 percent gain in the Nasdaq. The stock has retreated since, however.

Gilead Sciences

The number of shares sold short in this California-based research-based biopharmaceutical company surged more than 12 percent late in the month to nearly 26.23 million, or 12.3 percent of the float. The days to cover remained less than three, even as the average daily volume dropped to a year-to-date low. The year-to-date peak short interest was almost 40 million shares back in February.

European regulators offered good news for Gilead on its hepatitis C treatment in May. Shares ended the latest short interest period up more than 5 percent, though they were down fractionally at one point during those two weeks. This stock also has pulled back somewhat lately, and it is down more than 16 percent year-to-date.

Disclosure: At the time of this writing, the author had no position in the mentioned equities.

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