FDA panel to weigh second chance for new class of painkillers

By Steven Reinberg, HealthDay Reporter
FDA panel to weigh second chance for new class of painkillers
Trials halted in 2010 after some taking the drugs may have overworked damaged knees, needed surgery.

(HealthDay) -- A U.S. Food and Drug Administration advisory panel on Monday will weigh the wisdom of allowing new clinical trials of a class of powerful painkillers for osteoarthritis. The drugs may have worked so well for some patients that those patients wound up needing knee replacement surgery because they overworked their already damaged joints.

Studies of these painkillers were halted in 2010 because of this troubling side effect, and at the time Dr. Nancy Lane, lead researcher on a trial looking at one of these drugs, tanezumab, said patients who ended up needing a knee replacement most likely harmed their damaged joint even further because they felt so good.

"They probably accelerated the degeneration of the joint," said Lane, director of the Aging Center, Medicine and Rheumatology, at the University of California, Davis. "Sometimes, is good in protecting you."

However, there was some evidence that when these drugs were given with another common , a reaction occurred that might have caused the problem.

In addition to tanezumab, which is made by ., trials of two similar drugs were also stopped. These drugs were REGN475, made by Regeneron Pharmaceuticals, and fulranumab, made by Johnson & Johnson.

Now, the three companies are expected to argue that these drugs, known as anti-nerve growth factors (anti-NGFs), are needed by many patients suffering from . They are proposing to run trials using the drugs at lower doses and without other pain medications such as Advil. In addition, they are expected to tell the expert panel they will be more selective in which patients they recruit for their research.

One of the questions the panel is being asked to consider is whether, given the risk of these drugs, are there any groups of people who would benefit from them?

Dr. Elaine Tozman, an associate professor in the division of and immunology at the University of Miami Miller School of Medicine, said she doesn't think this new painkiller would add much to the treatment of osteoarthritis.

"This is really a drug which is for a symptom of osteoarthritis, it's really for pain," she said. "As rheumatologists, most of us are looking for a drug that works on the underlying disease."

Tozman noted that patients with severe osteoarthritis of the knee usually go on to have a joint replacement.

However, the companies will try to convince that panel that there are millions of people who could benefit from these drugs.

"Based on the assessments of risk and benefit, we conclude that further clinical investigation of tanezumab in osteoarthritis and other forms of is warranted with the protection of additional risk management and surveillance measures," Pfizer said in FDA briefing documents. "Chronic pain affects millions of adults in the United States. For many patients, treatment of chronic pain is inadequate in part due to the limitations in the availability of effective treatments and inadequate patient and clinician knowledge about the best ways to manage chronic pain."

For its part, Regeneron stated "... there may be a role for anti-NGF therapy in pain conditions where there is a high unmet need, i.e., those for which there are no adequate alternatives."

Although the FDA is not required to follow the recommendations of its advisory panels, it usually does.

Lane said tanezumab, which is given by injection, should probably not be used frequently. The effect of the drug can last at least eight weeks, she added, but no studies have been done yet on its long-term effects.

The works in a unique way by blocking nerve growth factor (NGF), which is essential for normal development of the nervous system but is also released when there is inflammation. NGF stimulates nerve cells and triggers pain, Lane explained.

"By inhibiting NGF, we really get a dramatic reduction in pain in patients who have pretty severe osteoarthritis," she said. "It doesn't do anything to the disease, it doesn't hurt your stomach, it doesn't change how you think or make you groggy. This is a real game-changer."

In addition to osteoarthritis, tanezumab was also being testing in patients with cancer pain, interstitial cystitis, chronic low back pain and diabetic nerve pain.

Some 27 million adults in the United States have osteoarthritis, with the knee being the most affected joint, according to the U.S. Centers for Disease Control and Prevention.

The number of people with osteoarthritis of the knee is expected to rise as baby boomers age and as obesity among Americans increases, Lane noted.

More information: For more on osteoarthritis, visit the U.S. National Library of Medicine.

Related Stories

New drug offers big relief for osteoarthritis pain

date Sep 29, 2010

A phase II clinical trial of the first new type of drug for musculoskeletal pain since aspirin shows that it significantly reduces knee pain in osteoarthritis, the most common osteoarthritis pain, according to new research ...

FDA links once-promising pain drugs to bone decay

date Mar 08, 2012

Some of the world's largest drugmakers will face an uphill battle next week in their bid to revive a class of experimental arthritis drugs that have been sidelined by safety concerns for nearly two years.

There's Hope for Debilitating Knee Pain

date Jan 14, 2010

(PhysOrg.com) -- Complaints about knee pain can be all too familiar when you suffer from osteoarthritis of the knee. The condition often keeps sufferers from participating in many activities—sometimes even ...

Recommended for you

US aims to cut antibiotic use

date Mar 27, 2015

US President Barack Obama on Friday rolled out plans to cut inappropriate antibiotic use by half, in an effort to tackle drug resistance.

Questions over value of new antibiotics to tackle resistance

date Mar 26, 2015

In the first installment of a new series, Peter Doshi, Assistant Professor at the University of Maryland School of Pharmacy and Associate Editor at The BMJ, asks why authorities are approving drugs with little evidence they d ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.