FDA rejects experimental painkiller Acurox

By Dr. Ananya Mandal, MDApr 23 2010

In a new development King Pharmaceuticals Inc. and Acura Pharmaceuticals Inc. have failed to win the approval of a US panel for marketing an experimental painkiller called Acurox.

Acurox contains a chemical called Oxycodone which is purported to prevent abuse. The outside panel of advisors for the US and Food Drug Administration believe that the data submitted by the companies is inadequate and does not show that there is any prevention of abuse liability with the use of Acurox. The panel agreed on not supporting the claim in a 19-1 vote at Gaithersburg, Maryland this Thursday.

Acurox is a short acting tablet that is a combination of Oxycodone and niacin. Both King and Acura have developed this drug together. They claim that although Oxycodone has drug abuse liability, Nicain can help act as abuse-deterrent. Too much of niacin can cause feeling of warmth and flushing of skin that may prevent abuse of this combination. The tablet cannot be crushed or melted for snorting. Acurox is promoted for moderate to severe pain. Acura had submitted a new drug application (NDA) for Acurox with the FDA on 30^th of December 2008 and was subsequently asked for more data and information.

According to Jeffrey Kirsch, Chairman of the Anesthetic and Life Support Drugs Advisory Committee, “What I’m hearing from the committee is that it’s probably not appropriate to put the niacin in this product because it does not have a definitive advantage, and it has associated side effects.” Taking Acurox with food, aspirin or other over-the-counter pain relievers seemed "sufficient to reduce the deterrent effect of niacin to make it no longer clinically relevant," Kirsch said. Thursday’s meeting was jointly chaired by Anesthetic and Life Support Drugs Advisory Committee and the Drug Safety and Risk Management Advisory Committee.

The approval was important for the companies. It is estimated that if approved Acurox may bring in a $58.3 million sales in for King Pharma in 2012. As a result King’s stocks fell 32 cents (2.8%) to $11.10 at 4 p.m. in New York Stock Exchange composite trading. Acura’s shares were halted during the panel meeting.

In a joint statement from representatives of both companies the companies promised that they “will work with the FDA to determine the next steps for the Acurox development program.” But they were hopeful that their concept of abuse deterration was praised by most of the panel members. King Chief Science Officer Eric Carter said, “They liked the science, they liked the concept…. They've given us the opportunity to go back and work with the FDA ... we're certainly going to be looking at a number of different options.” Dr. Bob Rappaport, head of the FDA division that was reviewing Acurox also said, “if they come back with a different set of data we'll probably come back to the committee.”