Efficacy and tolerability of DHEP-heparin plaster in reducing pain in mild-to-moderate muscle contusions: a double-blind, randomized trial

Abstract Objectives: To investigate if the 180-mg diclofenac epolamine and heparin sodium 5600?IU medicated plaster (DHEP-heparin) is more effective for pain reduction in mild-to-moderate contusions than the reference diclofenac epolamine 180?mg plaster (DHEP). Research design and methods: This multicenter, multinational, prospective, double-blind versus reference comparator and versus placebo, controlled trial had balanced random assignment in three parallel treatment groups. The DHEP-heparin medicated plaster was compared to the DHEP medicated plaster and a placebo medicated plaster. A total of 331 outpatients, aged ≥18 and ≤65 years, with unilateral mild-to-moderate muscle contusion, pain on standardized movement of ≥50?mm, and superficial hematoma of ≤10?×?14?cm(2) completed the study. Plasters were applied each morning, for ≥20 hours daily for 14 consecutive days. Outcomes were assessed in three visits, over 14 days, plus patients' daily self-assessment. Clinical trial registration: 05DCz/FHp11 - Eudra CT n: 2005-003829-31 Main outcome measures: Primary efficacy endpoint was mean change from baseline in pain on movement after 3 days of treatment, compared between groups. Secondary efficacy endpoints included mean daily change from baseline in pain on movement during treatment, pain level as assessed at control visits after 7 and 14 days, time (days) to hematoma disappearance based on patients' daily evaluations, rescue medication use, and overall treatment efficacy as judged by both patients and investigators. Results: Pain progressively declined in all groups, more rapidly in DHEP-heparin recipients, compared to DHEP, and in both active treatment groups compared to placebo. Adverse events were recorded in 24 of the 355 (6.7%) exposed patients, and generally resolved without need to interrupt treatment. Conclusion: The DHEP-heparin plaster is superior to the reference DHEP plaster in reducing pain associated with mild-to-moderate muscle contusion. Both active treatments were significantly more effective than placebo, and each showed a comparably favorable, placebo-like safety profile.