UPDATE 1-U.S. FDA asks Endo to withdraw Opana ER opioid; shares fall

(Updates with comment from FDA commissioner, background)

WASHINGTON, June 8 (Reuters) - The U.S. Food and Drug Administration said on Thursday it has asked Endo International Plc to withdraw from the market its long-lasting opioid painkiller Opana ER, sending the company's shares down more than 12 percent.

"After careful consideration, the agency is seeking removal based on its concern that the benefits of the drug may no longer outweigh its risks," the agency said in a statement.

The move comes after a panel of advisers concluded in March that the benefits of Opana ER, which was approved in 2006 and reformulated in 2012 to resist abuse, did not outweigh the risks. While nasal abuse rates fell, the rate of intravenous abuse increased.

The withdrawal marks the first time the agency taken steps to remove an opioid pain medication due to the public health implications and comes amid an intense national debate about the abuse of opioids. Opioids were involved in more than 33,000 deaths in 2015 and opioid overdoses have quadrupled since 1999, according to the Centers for Disease Control and Prevention.

"We are facing an opioid epidemic - a public health crisis, and we must take all necessary steps to reduce the scope of opioid misuse and abuse," Dr. Scott Gottlieb, the FDA's newly appointed commissioner said in a statement.

Opana ER has also been associated with a serious outbreak of HIV and hepatitis C, the agency said, as well as a serious blood disorder known as thrombotic microangiopathy.

The move coincides with a lawsuit filed on May 31 against the pharmaceutical industry by Ohio, charging that a number of companies, including Endo, Purdue Pharma, Teva Pharmaceutical Industries Ltd, Johnson & Johnson and Allergan Plc conducted misleading marketing campaigns that downplayed the drugs' addictiveness. Some other states and cities have filed similar lawsuits.

Gottlieb said the agency will "continue to take regulatory steps when we see situations where an opioid product's risks outweigh its benefits, not only for its intended patient population but also in regard to its potential for misuse and abuse."

Endo's shares fell 12.2 percent to $12.10 in extended trading.

(Reporting by Toni Clarke in Washington; additional reporting by Ankur Banerjee; Editing by Chris Reese and Lisa Shumaker)