Risk of Endo's opioid painkiller outweigh benefits: FDA panel

Pills and bottles (VladimirSorokin)

The benefits of Endo International Plc's long-acting opioid painkiller no longer outweigh its risks, an independent panel to the U.S. Food and Drug Administration (FDA) concluded on Tuesday.

The advisory committee meeting was called to address the high abuse rate of Endo's Opana ER and other oxymorphone formulations, as the health regulator looks to stem the tide of opioid abuse, overdose and addiction.

Deaths involving opioids - including prescription painkillers, heroin and other street drugs - have catapulted in recent years. The Centers for Disease Control and Prevention estimates at least 91 Americans succumb every day to opioid overdose.

Opana ER is a long-acting variation of oxymorphine that is intended to treat pain severe enough to require daily, around-the-clock, long-term opioid treatment.

Initially approved in 2006, a new formulation of Opana ER designed to deter snorting and oral abuse hit the market in 2012.

Data shows that while nasal abuse has reduced with the reformulation, intravenous abuse has increased, FDA staff noted in an internal review on Thursday, acknowledging that it was unclear whether that rise was tied directly to the reformulation.

This trend was apparent before the reformulation hit the market, and abuse rates are similarly high for oxymorphone generics, they said.

Of particular concern is the increased rate of certain rare blood disorders and HIV that are linked to the shift in route of Opana abuse from nasal to intravenous, panelists said on Tuesday.

Eighteen panelists recommended that the benefit of the Opana reformulation continues to eclipse the risk of serious side-effects, while eight disagreed and one member abstained from voting.

The FDA typically follows the recommendations of the panel but is not obliged to do so.

Endo's shares closed down about 4 percent on Tuesday.