US FDA staff see potential to abuse Covidien drug

* FDA staff says Exalgo has “high abuse potential”

* FDA to ask advisers about drug’s risks

* Agency’s outside advisors meet Wednesday

WASHINGTON, Sept 22 (Reuters) - Neuromed Pharmaceuticals Inc and Covidien's COV.N experimental, longer-lasting opioid pain drug is prone to abuse and overdose as it can easily be crushed by biting the tablet, according to U.S. Food and Drug Administration staff reviewers.

In documents released ahead of a public meeting on Wednesday to discuss Exalgo, FDA staff said crushing it would instantly release the painkiller’s powerful effects.

“Overall, this product has a high abuse potential and has the same safety concerns observed by other similar extended-release highly potent opioid drug products that are abused and diverted,” the staff wrote in documents released late Monday.

Neuromed, which sold its U.S. rights to Exalgo to Covidien in June, is seeking FDA approval to market the extended-release hydromorphone drug to patients with moderate-to-severe pain who have developed a tolerance to other opioid pain medications.

Unlike other forms of hydromorphone pain relievers on the market that need to be taken every four to six hours, Exalgo aims to be taken less frequently.

Hydromorphone is available in shorter-release formats by a variety of drugmakers, including generic companies. Janssen Pharmaceuticals, a Johnson & Johnson JNJ.N company, sells an extended-release version in Europe under the brand name Jurnista.

The FDA is particularly concerned about the potential for abuse with longer-lasting hydromorphone after Purdue Pharma’s version, called Palladone, was pulled from the market in 2005 over serious interactions with alcohol.

At the meeting on Wednesday, FDA officials will ask a panel of outside advisers to weigh just how risky Exalgo is compared with other opioids and what kind of steps should be taken to help prevent abuse if the drug is approved.

The agency is not bound by the recommendations of its outside advisors but usually follows them. Neuromed has said it expects an FDA decision by Nov. 22.

Common side effects with hydromorphone include dizziness, drowsiness, constipation and stomach pain. It can also lead to difficulty breathing or fainting.

The FDA posted the documents on its website at (Reporting by Susan Heavey; Editing by Lisa Von Ahn)