Enrolling Clinical Trials for Pain Treatment

By Ted Swing, Ph.D

The development of new treatments for pain depends on clinical trials to demonstrate the safety and efficacy of these treatments. As part of our commitment to advancing the field of pain treatment, we are taking part in several clinical trials evaluating such new treatments.

Advantages and Limitations of Clinical Studies

In many cases, these studies involve delivering cutting-edge treatments that can provide a medical benefit to patients for no cost. Additionally, patients may obtain medical evaluations as part of the study follow up that can be useful to them. It is also important for patients to be aware, though, that even for patients who qualify to take part in a study, a benefit is not guaranteed. Most clinical trials involve randomization, with some patients being assigned to an untreated comparison group — often patients are not told which treatment they are receiving. Even those treated may fail to benefit from the treatment. However, by taking part in the study, patients are helping to advance the science of pain treatment in ways that can help many patients in the future.

VertiFlex Totalis Trial

One of the more common causes of chronic pain, affecting millions of Americans, is spinal stenosis. Spinal stenosis refers to a narrowing of the central canal of the spine through which the spinal cord runs. For some patients, they are simply born with a more narrow central canal, but it can also become narrowed over time by degeneration of the joints in the spine (facet arthrosis), a misalignment of the vertebrae and discs (spondylolisthesis) or the thickening of a ligament that runs through the spine (ligamentum flavum hypertrophy). As the space narrows, this can put pressure on the spinal cord, causing pain that radiates; in the case of the spinal stenosis in the lower back it will radiate down into the buttocks or legs.

The VertiFlex Totalis trial is evaluating a treatment for spinal stenosis in the lower back causing pain that radiates down into the legs. Specifically, this treatment is for those whom thickening of the ligament causes their stenosis. Typically, patients with stenosis causing chronic pain may try conservative care (rest, physical therapy, chiropractic care), medications and epidural steroid injections. If they do not improve and are in moderate to severe pain, they may get surgery. The Totalis procedure is a less invasive alternative to surgery for treating stenosis. Rather than performing an open surgery of the spine, a metal tube is inserted between the bones in the spine and instruments are guided through this tube using x-ray imaging. A small part of the ligament is removed in the area where it is putting pressure on the spinal cord to permanently relieve that pressure and the pain that it causes. This procedure is already FDA approved, however VertiFlex is conducting this trial in cooperation with Medicare to help Medicare evaluate if they will be reimbursing the procedure for their patients.

Patients who are age 55 or older and have spinal stenosis in the lumbar spine caused by the thickening of this ligament may qualify to take part in this study. For those who qualify and enroll in the study, two-thirds will receive the treatment procedure whereas one-third will receive a non-treatment comparison procedure. Patients will then be followed up for up to two years after the procedure. For those non-treated patients, if they continue to experience pain for some time after the procedure, it is possible for them to exit the study and receive the Totalis procedure paid for by VertiFlex.

Grunenthal CRPS Trial

Complex regional pain syndrome (CRPS), also known as reflex sympathetic dystrophy (RSD), is a chronic pain condition occurring in the extremities. CRPS is generally caused by a traumatic injury. In certain cases, this traumatic injury can cause an abnormal response in the nervous system that leads to chronic pain as well as other symptoms including hypersensitivity and discoloration of the affected limb. This condition is often treated with medications and implanted devices such as spinal cord stimulators, but lasting relief is difficult for some patients.

Grunenthal is testing a drug, neridronate, that can be delivered to patients in a series of infusions to potentially produce lasting relief from CRPS pain. Neridronate is from a class of drugs currently used for treating conditions such as bone cancers. A study from Italy published in 2013 found this drug to be effective in relieving CRPS pain. The current Grunenthal study is intended to test this treatment for possible approval for treating CRPS in the US. Qualifying patients who enroll in the study will receive a series of four supervised infusions over a two-week period. Two-thirds of these patients will receive infusions of neridronate, with one-third getting non-treatment infusions for comparison. Patients will complete 12 months of follow up to evaluate the efficacy of the treatment.

If you are interested in learning if you are qualified, you can discuss this with your pain management providers. For additional information about this study you can contact me directly at TedS@arizonapain.com.

Ted Swing has more than ten years of research experience and four years of teaching experience in psychology, has published in top psychology and medical journals, and has presented his research at major conferences. He received his Ph.D. in Social Psychology from Iowa State University and has been the Research Director at Arizona Pain since May 2012.