Updated with new information. BEDMINSTER, NJ ( TheStreet) --The U.S. Food and Drug Administration on Thursday approved a prescription fish-oil pill from Amarin ( AMRN - Get Report) that will be used to treat patients with very high levels of triglycerides, a type of fat found in blood. Amarin's newly approved drug Vascepa is made from ultra-purified ethyl EPA, an omega-3 fatty acid commonly found in fish. An FDA spokesperson confirmed the approval. An FDA decision on whether Vascepa will be granted five years of market exclusivity as a New Chemical Entity (NCE) has not been announced and won't likely be public until August, Amarin said in a statement. Shares of Amarin were halted ahead of the Vascepa approval announcement at $15.31. When taken daily at its highest dose, Vascepa lowered triglyceride levels by 33% compared to a placebo in a phase III clinical trial that enrolled patients with very high baseline levels (greater than 500 mg/dl) of the blood fat. Vascepa also did not cause a significant increase in LDL, or "bad" cholesterol. Vascepa will compete against a similar prescription-grade fish oil pill marketed by GlaxoSmithKline ( GSK - Get Report) known as Lovaza, which generates about $1 billion in annual sales. Amarin is planning on a Vascepa commercial launch in the first quarter of 2013. Who launches the drug is still being determined. Amarin said it is still pursuing three options: A sale of the company, a partnership or marketing the drug on its own. --Written by Adam Feuerstein in Boston. >To contact the writer of this article, click here: Adam Feuerstein. >To follow the writer on Twitter, go to http://twitter.com/adamfeuerstein. >To submit a news tip, send an email to: email@example.com. Follow TheStreet on Twitter and become a fan on Facebook.