Two members of the Center for Pain Research and Innovation have been awarded a U01 grant from the NIDCR (National Institute of Dental and Craniofacial Research; NIH) to investigate propranolol and its use in treating temporomandibular disorder (TMD). The grant award totals $3,254,644 over three years.
Dr. Inna Tchivileva, research assistant professor in the Department of Endodontics, and Dr. Gary Slade, John W. Stamm Distinguished Professor in the Department of Dental Ecology and director of the UNC Oral Epidemiology PhD program, will conduct a research project entitled, “SOPPRANO” (Study of Orofacial Pain and PropRANOlol). The SOPPRANO study is a phase III, randomized, placebo-controlled clinical trial aimed at evaluating the efficacy of propranolol for treatment of pain in patients with temporomandibular disorder (TMD). Propranolol is a beta-blocker widely used to treat a number of conditions including cardiac disorders, migraine and cluster headaches, glaucoma, and psychiatric conditions including anxiety, post-traumatic stress disorder and phobias.
Tchivileva summarized the study by explaining, “TMD-related pain is perpetuated by enhanced activity of the adrenergic system – which is a part of the nervous system identified by organs which use adrenaline and noradrenaline as neurotransmitters – and blocking this activity with propranolol may reduce pain. In addition, enzymes, such as catechol-O-methyltransferase (COMT), regulate the adrenergic system and affect pain perception. The enzyme activity can depend on variations within the enzyme’s genes; for example, in the COMT gene, these variations have been associated with enhanced pain and risk of developing TMD. In an earlier study, I found that the analgesic effect of propranolol varied among TMD patients and was associated with variations in the COMT gene. This larger study will allow us to further evaluate propranolol efficacy in treatment of painful TMD and the role of the COMT gene as a predictor of response to propranolol.”
This study will enroll 200 participants with TMD at two academic medical centers (the University of North Carolina at Chapel Hill and the University of Florida). Participants will be randomly assigned to receive propranolol or placebo in a double-blind fashion. Results from this 12-week study may potentially lead to the development of individually tailored therapy based on a pharmacogenetic approach that can be applied to patients suffering from pain induced by TMD and other conditions.