Abstract
INTRODUCTION: Topical nonsteroidal anti-inflammatory drug (NSAID) formulations provide significant pain relief with excellent tolerability in the local treatment of soft tissue injuries. This study aimed to assess the efficacy and safety of a novel etofenamate 70 mg medicated plaster for treatment of pain in patients with acute sprains, strains and contusions (bruises). METHODS: In this randomized, placebo-controlled trial patients with acute injuries of recent onset received etofenamate or placebo plasters (2:1) applied once daily for 7 days. Regular clinical assessments were made with focus on pain on movement (POM) in millimetres on a 100-mm visual analogue scale (VAS). RESULTS: A total of 180 adult patients (mean age 34.5 ± 13.5 years; 49.4% female) were enrolled. Mean VAS values for POM were 70.0 ± 6.3 mm at baseline; at 72 h POM had reduced by 59.0 mm and 33.3 mm in the etofenamate and placebo groups, respectively. Least squares mean treatment difference was 25.0 mm (p value for analysis of covariance < 0.0001). Results were consistent across type of injury (sprain/strain or contusion). Clinically meaningful superiority of etofenamate versus placebo was also seen for POM at the 24-, 48-, 96- and 120-h visits (p < 0.0001). Time to reach meaningful (30%), optimal (50%) and complete (100%) reduction of POM was significantly shorter with etofenamate. A significantly greater proportion of patients using etofenamate rated their progress and/or treatment as 'good' or 'very good'. The responder rate (proportion of patients with at least 50% pain reduction at 72 h) was 98.3% for etofenamate and 38.3% for placebo, resulting in a number needed to treat of 1.7, a value consistent with high effectiveness. The plasters adhered well over the 24-h dosing period and were very well tolerated. CONCLUSION: In the setting of acute sprains, strains and contusions (bruises) the etofenamate plaster has therapeutic efficacy that is comparable to that for the best available topical NSAID formulations. REGISTRATION: 2021-003778-30 (EudraCT number).