Study of Orofacial Pain and PropRANOlol

Study Summary

Purpose: Primary: To evaluate the efficacy of extended-release (ER) propranolol compared to placebo in the reduction of a pain index in patients with temporomandibular disorder (TMD). Secondary: To determine if extended-release propranolol efficacy varies according to participants' catechol-O-methyltransferase (COMT) genetic polymorphisms and to investigate the efficacy of extended-release propranolol compared with placebo using secondary endpoints. Exploratory: To investigate whether the efficacy of extended-release propranolol in the reduction of the pain index varies according to participants' polymorphisms in 3 other genetic regions and according to various phenotypic characteristics. Participants: 200 patients with chronic TMD will be randomly assigned, in a 1:1 parallel, double-blind fashion, to receive either extended-release propranolol or placebo at one of three study sites: University of North Carolina-Chapel Hill School of Dentistry; University of Florida-Gainesville College of Dentistry; and the State University of New York at Buffalo School of Dental Medicine. Procedures (methods): Randomization will be to either propranolol or placebo. The 10-week study treatment period is divided into: 1 week of drug titration, 8 weeks of drug maintenance, and 1 week of drug tapering. The titration and tapering doses are 60 mg (capsules) once per day orally; the maintenance dose is 60 mg twice per day orally. Participants will attend 6 clinic visits over 12-15 weeks as follows: screening and baseline visit (Visit \[V\] 0, 7-21 days prior to V1); randomization and start of treatment (titration) (V1, study day 0); maintenance visit 2 (V2, 1 week post-randomization, study day 7+3); maintenance visit 3 (V3, 5 weeks post-randomization, study day 35 +/- 7); tapering visit (V4, 9 weeks post-randomization, study day 63 +/- 7); and tapering visit 5 (V5, 11 weeks post-randomization and 1 week after drug tapering ends, study day 77 +/- 7). Depending on the visit, procedur

Primary Outcome

Weekly mean pain index computed as the arithmetic mean of daily pain index values during the week prior to randomization and prior to each study visit. Daily pain index is computed as pain intensity (0-100 numeric rating scale where 0 = "no pain" and 100 = "the most intense pain imaginable") multiplied by pain duration (0-100 percentage scale where percent = "percent of waking day you had facial pain") as reported in the Daily Symptom Diary and divided by 100. The pain index range is from 0 to 1

Interventions

• DRUG Placebo
• DRUG Propranolol ER