VIENNA — Americans attending the annual European Congress of Rheumatology are often impressed by the discussion of unfamiliar, even exotic therapies not available in the United States. The most intriguing of these are supported by encouraging clinical trials data. Yet many of the therapies may never reach the U.S. market because they are the property of small companies that find the Food and Drug Administration approval process too fiscally daunting.
Here is a sample of novel therapies, currently unavailable in the United States, that were the subject of research presentations at the meeting, sponsored by the European League Against Rheumatism.
▸ Diacerein. This plant-derived anthraquinone derivative blocks the downstream proinflammatory effects associated with stimulation of the interleukin-1 receptors located on chondrocytes and inflammatory cells. It does not affect prostaglandin synthesis.
EULAR guidelines categorize diacerein as a symptomatic slow-acting drug for both knee and hip osteoarthritis (OA). It is widely used for this purpose in much of Europe, where it has been the subject of more than a dozen randomized controlled trials. At the EULAR meeting, Worowit Louthrenoo, M.D., presented the first randomized double-blind controlled trial of diacerein in an Asian population.
The Thai study involved 161 OA patients randomized to 50 mg b.i.d. of diacerein or 10 mg b.i.d. of piroxicam for 16 weeks, with an additional 8 weeks of follow-up post discontinuation. The primary end point in the TRB Chemedica-sponsored trial was pain relief as reflected in WOMAC scores. At week 16, the diacerein group showed a mean improvement of 70% in WOMAC scores, compared with baseline—not significantly different from the 74% improvement in the piroxicam group. However, at week 20—which was 4 weeks following discontinuation—the mean improvement in the diacerein group remained at 67%, compared with 47% for piroxicam. And at week 24, the diacerein group maintained a 70% improvement in WOMAC scores, versus a 27% improvement in the piroxicam group, said Dr. Louthrenoo, professor of medicine at Chiang Mai (Thailand) University.
The most frequent adverse event in the diacerein group was diarrhea; it was less common than the abdominal pain reported by piroxicam users.
▸ Nuclear magnetic resonance therapy for low back pain. That's right—MRI not for imaging purposes, but as treatment. Therapeutic MRI, called MultiBioSignal Nuclear Resonance Therapy (MBST) was developed by a German company, Medtec Medizintechnik GmbH, after physicians serendipitously noted that patients with disabling chronic low back pain who had to undergo repeated conventional MRIs because of technical imaging problems reported feeling much better afterward.
Physicians and physicists came up with a basic science rationale to explain the effect, then modified conventional MRI equipment to enhance it. They created a device that generates a static magnetic field and a three-dimensional alternating radiofrequency field designed to induce resonant vibration of hydrogen atoms within cartilage and bone in order to stimulate cell proliferation. Investigators at the University of Munich have previously demonstrated that MBST increases cartilage thickness in patients with knee osteoarthritis.
Sound flaky? Medical officials at one of Austria's largest workers' compensation insurer-funded inpatient rehabilitation centers don't think so, Werner C. Kullich, Ph.D., told this newspaper.
He explained that the prevailing workers'-comp philosophy in German-speaking Europe is that rehabilitation of patients with chronic disabling low back pain is best accomplished through a 3- to 4-week inpatient stay at specialized centers that provide multimodal therapy, including extensive education, exercises, massage, hydrotherapy, and electrical stimulation. The results, though shown to be superior to the outpatient therapies that are the norm in much of the rest of the world, leave much to be desired—thus the insurance industry's interest in MBST and other novel approaches.
Dr. Kullich presented an insurer-sponsored, double-blind, placebo-controlled trial of MBST versus sham therapy in 62 rehab-clinic patients with chronic low back pain. In addition to the standardized intensive 3-week inpatient rehab program, study participants received hour-long MBST or sham therapy sessions on 5 consecutive days. The study end points were changes in pain and function at 1 and 12 weeks post MBST.
Both groups showed significant improvements in low back pain as assessed by the Roland-Morris Questionnaire at 1 week; by 3 months, however, scores in the rehabilitation-plus-placebo group had retreated to baseline levels, while the MBST group showed further significant improvement.
Similar results were seen on the Oswestry Disability Questionnaire. Particularly striking was the finding that after 3 months 74% of MBST-treated patients rated their ability to provide personal care as improved, and none indicated it had deteriorated, compared with baseline. In contrast, only 37% of controls rated their personal care capability as improved, while 11% said it had deteriorated. Walking, sitting, standing, and lifting were areas where both groups showed significant improvement at 3 months, with greater gains recorded in the MBST group, said Dr. Kullich of the Ludwig Boltzmann Institute for Rehabilitation of Internal Diseases in Saalfelden, Austria.