FDA Ruling Shakes Up Biotech: Gilead, AbbVie And More

• Biotechs have had a tough week. On Wednesday, stocks plummeted after Citron Research released a new report classifying Valeant Pharmaceuticals Intl Inc VRX as a "pharmaceutical Enron."
• On Thursday, shares continued to tumble on the news and an FDA report warning that AbbVie Inc ABBV's Viekira Pak and Technivie could cause serious liver injury.

Many major biotech stocks tumbled after the FDA warned AbbVie’s Viekira Pak and Technivie, used to treat hepatitis C, could cause serious liver injury, especially in patients with underlying advanced liver disease.

As a result, shares of AbbVie fell 10.33 percent on Thursday. However, one stock benefited from the news: Gilead Sciences, Inc. GILD, which rose 5.77 percent.

Viekira Pak was worrying Gilead investors, as the drug offered a cheaper option to Gilead’s Hepatitis C treatment. Now the path may be clearer for Gilead’s Harvoni, which now looks safer than Viekira or Technivie.

Related Link: Noted Biotech Analyst Doesn't Think Valeant And Horizon Are Frauds, But Did Push A Line

Other stocks on the decline include:

• Valeant Pharmaceuticals Intl Inc VRX, down 7.08 percent
• Horizon Pharma PLC HZNP, down 11.53 percent
• Express Scripts Holding Company ESRX, down 4.13 percent
• Enanta Pharmaceuticals Inc ENTA, down 40.62 percent

Disclosure: Javier Hasse holds no positions in any of the securities mentioned above.