Despite being one of the most successful sectors in the past few years where the markets produced substantial returns, the biotech sector has been struggling as of late. Most investors probably have seen this industry in the news quite a bit, but they may not realize the effects of this industry’s decline. The biotech industry has strong ties to the healthcare sector, one that many investors are tied to in one way or another in their portfolios.

Friday was an especially tough day for many biotech stocks, and below are 5 that suffered losses of at least 5% on the day.

Acadia Pharmaceuticals (ACAD - Snapshot Report)
Acadia focuses on the discovery, development and commercialization of small molecule drugs for the treatment of central nervous system disorders. On Friday, the stock saw a decrease of -7.60%, closing the day at $34.15 per share. ACAD is currently a Zacks Rank #4 (Sell).

ANI Pharmaceuticals (ANIP - Snapshot Report)
ANI Pharmaceuticals engages in developing, manufacturing, and marketing branded and generic prescription pharmaceuticals. The company is currently a Zacks Rank #5 (Strong Sell) and on Friday suffered a decline of -6.47% as of market close.

Bluebird Bio Inc. (BLUE - Snapshot Report)
Bluebird Bio Inc is a biotech focused on the development, manufacture, and marketing of therapies for severe disorders. The company suffered a decline of -9.69% on Friday, and currently holds a Zacks Rank #4 (Sell).

Orexigen Therapeutics Inc. (OREX - Analyst Report)
Orexigen Therapeutics Inc is a biopharmaceutical company focused on the development of pharmaceutical product candidates for the treatment of central nervous system disorders, including obesity. The company currently holds a Zacks Rank #4 (Sell). OREX had dropped -7.14% as of market close.

Alder Biopharmaceuticals (ALDR - Snapshot Report)
Alder Biopharmaceuticals currently holds a Zacks Rank #4 (Sell) and is a clinical-stage biopharmaceutical company that discovers, develops, and seeks to commercialize therapeutic antibodies. As of market close on Friday, the stock was down a substantial -9.25% to $33.86 a share.

Bottom Line

The biotech sector has had a rough time lately. It will be something to watch as this industry attempts to turn things around and finish out 2015 on a high note.