Safety and Efficacy of the FLECTOR (Diclofenac Epolamine) Topical System in Children with Minor Soft Tissue Injuries: A Phase IV Non-randomized Clinical Trial

Clin Drug Investig. 2022 Jan;42(1):43-51. doi: 10.1007/s40261-021-01101-x. Epub 2021 Nov 26.

Abstract

Background and objective: A topical formulation of diclofenac (FLECTOR diclofenac epolamine topical system (FDETS)) is approved in adults for the treatment of acute pain due to minor strains, sprains, and contusions; however, its safety and efficacy have not been investigated in a pediatric population. This study assessed the safety and efficacy of the FLECTOR (diclofenac epolamine) topical system in children.

Methods: This was an open-label, single-arm, phase IV study at ten USA-based family medicine or pediatric practices in children aged 6-16 years with a clinically significant minor soft tissue injury sustained within the preceding 96 h and at least moderate spontaneous pain on the Wong-Baker FACES® Pain Rating Scale. The FLECTOR topical system was applied twice daily until pain resolution or Day 14. The primary endpoint was local tolerability and systemic safety. Key secondary endpoints were diclofenac plasma concentrations and analgesic efficacy.

Results: 104 patients were enrolled; 52 were 6-11 years old, and 52 were 12-16 years old (mean age 11.6 years). The maximum tolerability score experienced by any patient was 1 (faint redness). Fourteen adverse events (none serious) in nine patients (8.7%) were considered possibly treatment-related. Reduction in pain during the study was somewhat greater for patients aged 6-11 versus 12-16 years (p < 0.011). The diclofenac plasma concentration tended to be higher in the younger age group compared with older patients: 1.83 versus 1.46 ng/mL at the first assessment and 2.49 versus 1.11 ng/mL at the last assessment (p = 0.002).

Conclusion: The FLECTOR topical system safely and effectively provided pain relief for minor soft tissue injuries in the pediatric population, with minimal systemic nonsteroidal anti-inflammatory drug exposure and low potential risk of local or systemic adverse events.

Clinical trial registration: ClinicalTrials.gov identifier NCT02132247.

Plain language summary

In this post-marketing clinical trial, the safety and efficacy at relieving pain of the FLECTOR diclofenac epolamine topical system (FDETS), a nonsteroidal anti-inflammatory drug (NSAID) formulation in a medicated patch, was assessed in a pediatric population (aged 6–16 years) with clinically significant minor soft tissue injuries. The safety and efficacy profiles in the pediatric population were consistent with previous data in adults. Both diclofenac plasma concentrations and reduction in pain during the study were greater for younger patients (aged 6–11 vs. 12–16 years), but plasma concentrations were much less than after diclofenac was taken orally in previous studies. This study shows that FDETS can safely and effectively provide pain relief for soft tissue injuries in children, with minimal systemic NSAID exposure and a low potential risk of either local or systemic adverse events.

Publication types

  • Clinical Trial, Phase IV

MeSH terms

  • Acute Pain* / drug therapy
  • Administration, Topical
  • Adolescent
  • Anti-Inflammatory Agents, Non-Steroidal / adverse effects
  • Child
  • Diclofenac / adverse effects
  • Diclofenac / analogs & derivatives
  • Humans
  • Pyrrolidines
  • Soft Tissue Injuries* / drug therapy

Substances

  • Anti-Inflammatory Agents, Non-Steroidal
  • Pyrrolidines
  • diclofenac hydroxyethylpyrrolidine
  • Diclofenac
  • epolamine

Associated data

  • ClinicalTrials.gov/NCT02132247