Zohydro has some competition.
Just days after drug maker Zogenix Inc. (NASDAQ: ZGNX) began sales of the first pure hydrocodone painkiller in the United States, Purdue Pharma said it was in the final stages of developing its own extended release formula for hydrocodone with abuse deterrent properties.
Zogenix has been sharply criticized for launching Zohydro without an abuse deterrent formula to discourage drug abusers from crushing or liquefying the painkiller so it can be snorted or injected. Some addiction treatment experts warn it could fuel a new wave of narcotic addiction and overdose deaths.
In a Phase III study, Purdue Pharma said its extended-release formulation of hydrocodone gave significant relief to patients with chronic low back pain. In addition to having abuse-deterrent properties, Purdue says the drug is designed for once a day use. Zohydro is meant to be taken twice a day to relieve chronic pain.
“We are very encouraged by the results of this pivotal study,” said Gary L. Stiles, MD, Purdue Pharma’s Senior Vice President of Research and Development. “This is another step forward in our efforts to develop therapeutic options for use by chronic pain patients that are designed to be unattractive to drug seekers.”
In a study of 588 patients with moderate to severe back pain, a majority who were treated with hydrocodone experienced at least a 30% improvement in pain relief. Nearly half of the patients (48%) achieved a 50% improvement. Side effects included constipation, nausea, vomiting, dizziness, and headache, which are typically associated with opioid painkillers.
Purdue says it plans to file a New Drug Application with the FDA later in 2014 requesting approval to market the medication.
Last week Zogenix said it was making “excellent progress” towards developing an abuse deterrent formula for Zohydro, but it was at least two years away.
The company has claimed Zohydro is actually safer than other hydrocodone drugs already on the market because it does not contain acetaminophen, which at high doses can cause liver damage. Hydrocodone combination drugs such as Vicodin are the most commonly prescribed painkillers in the U.S. with over 130 million prescriptions annually.
Meanwhile, Food and Drug Administration Commissioner Margaret Hamburg defended the agency’s approval of Zohydro, saying the painkiller offered a “unique” option to help treat pain.
Hamburg was “confronted” by West Virginia Senator Joe Manchin before a Senate hearing and asked to respond to a series of letters Manchin has written questioning the FDA’s decision to approve Zohydro over the objections of its staff and advisory committee.
“We recognize that this is a powerful drug, but we also believe that if appropriately used, it serves an important and unique niche with respect to pain medication and it meets the standards for safety and efficacy,” Hamburg said at a hearing of the Senate’s Health, Education, Labor and Pensions Committee.
“Americans are abusing, and many cases dying, at an alarming rate from highly addictive pain medicine, and it is shameful that the FDA would ignore its own experts to approve this drug,” Sen. Manchin said in a statement.
“Zohydro is ten times more addictive than any hydrocodone painkiller, and lacks any abuse-deterrent features. It cannot be released to the market, and I am concerned it was approved for all the wrong reasons.
Manchin has also asked for an investigation of allegations that Zogenix and other drug companies paid $25,000-$35,000 to attend private meetings with FDA officials. The senator said the meetings raised questions about whether the drug companies were buying influence over FDA decisions.
“I am pleased that Commissioner Hamburg personally guaranteed that she would respond to our letters and further discuss with me the deeply troubling pay-to-play allegations and the FDA’s approval of Zohydro over its own advisory panel’s recommendations,” said Senator Manchin.
“Americans and West Virginias need to have confidence that their government is acting in their best interests and not allowing special interests to buy a seat at the table to push their own financial agenda. The pay-to-pay allegations call into question whom the FDA is working for and the American people deserve to know the truth.”