Biologic Therapy Effective in Treating Cervical Disc Herniations
Cervical Disc Herniation
Successful treatment of cervical disc herniations with a biologic therapy would constitute a major breakthrough in spine care, potentially sparing patients from invasive procedures and a raft of ineffective nonoperative therapies. A new open-label study provides preliminary evidence that TNF-alpha inhibitors may reduce pain and disability in these patients. However, the authors caution that more research will be necessary before doctors can confidently offer this treatment to their patients.
In a randomized controlled trial, researchers from Seoul, South Korea and Rush University Medical Center in Chicago enrolled 49 patients (average age 45 years) with symptomatic cervical disc herniations confirmed on MRI. The patients had experienced symptoms for an average of 15 months.
Twenty-six patients received treatment with a TNF-alpha inhibitor (23 with infliximab and three with etanercept), according to Sanjung Lee, MD. Another 23 patients received nonoperative therapies, including physical therapy and nonsteroidal anti-inflammatory drugs. Dr. Lee presented the results at the recent annual meeting of the North American Spine Society in Philadelphia.
Infliximab and etanercept are powerful drugs that block the activity of tumor necrosis factor alpha, a molecule that appears to play an important role in regulating a variety of inflammatory conditions, including painful disc herniations.
Among patients who received the TNF-alpha inhibitors, pain scores one year later dropped dramatically and significantly (minus 3 points on a 10-point scale). By contrast, improvement in the control group was not significant (minus 1.4 points).
Scores on the Oswestry Disability Index were likewise significantly improved in the experimental group (minus 12.4 points, from 36 to 23.6), but not in the control group (minus 2.3 points, from 24 to 21.7). Temporary side effects included one patient with general myalgia, three with low fever, and two who complained of itching.
The authors said that some patients receiving a TNF-alpha inhibitor appeared to do better than others. Those with central and posterolateral focal lesions and minimal root compression tended to do well. Those with a combination of posterolateral lesions and massive root compression fared worse.
Dr. Lee called the results "encouraging," but pointed out that the therapy is relatively expensive, its indications unclear, and its results not uniformly successful. He counseled physicians tempted by the off-label therapy to choose their patients with care.
History supports a cautious approach. For example, in the last few years open-label studies and retrospective case series of TNF-alpha inhibitors in patients with sciatica showed tremendous initial promise. Some clinics began offering the therapy with enthusiasm. (Spine 2003; 28:750-3; Curr Med Res Opin 2004; 20:1075-85.)
But the first carefully controlled randomized trial provided a sobering reminder that early hopes for novel therapies are frequently dashed in rigorous trials. The study, led by Finn Jaro Karpinnen, MD, PHD, randomly allocated 40 patients with sciatica to receive a single intravenous infusion of either infliximab or saline. At the end of 12 weeks, pain and disability among those taking infliximab was no better than among those receiving placebo. (Presented at the annual meeting of International Society for the Study of the Lumbar Spine, Spine Week 2004, Porto, Portugal; unpublished.)
Dr. Lee, mindful of the limitations of the new study, recommended further study of TNF-alpha inhibitors in the cervical spine. "Further prospective, controlled, long-term trials comparing other treatments such as surgery and injections will be needed to better determine the indications [for] these drugs and the cost-benefit ratio," he and his colleagues concluded.
The North American Spine Society (NASS) is a multidisciplinary organization that advances quality spine care through education, research, and advocacy. www.spine.org