Low-dose SoluMatrix diclofenac : a review of safety across two Phase III studies in patients with acute and osteoarthritis pain.

INTRODUCTION: Similar to other NSAIDs, diclofenac is associated with serious dose-related cardiovascular, gastrointestinal, and renal adverse events. Low-dose SoluMatrix diclofenac , containing submicron particles of diclofenac, was developed to provide effective analgesia at lower drug doses compared with currently available NSAIDs. AREAS COVERED: The efficacy and safety of low-dose SoluMatrix diclofenac was evaluated in two randomized, placebo-controlled Phase III studies: a study in patients with acute pain following bunionectomy surgery and a study in patients with osteoarthritis pain of the hip or knee. In this review article, we summarize safety data from these studies. EXPERT OPINION: The safety results from the Phase III studies indicate that all dosing regimens of low-dose SoluMatrix diclofenac up to 12 weeks are generally well tolerated. Few serious gastrointestinal, cardiovascular, renal, or hepatic adverse events commonly associated with NSAID use were reported in these studies. Although not directly compared, the safety of SoluMatrix diclofenac was similar to findings for other diclofenac drug products. The potential for safe and effective management of acute and chronic pain at reduced NSAID doses is attractive; definitive characterization of SoluMatrix diclofenac safety requires confirmation by long-term studies.

Low-dose SoluMatrix diclofenac in the treatment of osteoarthritis: A 1-year, open-label, Phase III safety study.

INTRODUCTION: Diclofenac is used for the treatment of osteoarthritis (OA); however, like other nonsteroidal anti-inflammatory drugs (NSAIDs) it can be associated with serious dose-related adverse events (AEs). Low-dose SoluMatrix® diclofenac has been developed to provide efficacy at lower diclofenac doses. A recently published Phase III study evaluated the efficacy and safety of SoluMatrix diclofenac 35 mg twice daily (b.i.d.) and thrice daily (t.i.d.) in patients with OA pain treated for 12 weeks. METHODS: This Phase III multicenter, open-label study assessed the safety of SoluMatrix diclofenac in patients with OA dosed up to 52 weeks (ClinicalTrials.gov: NCT01510912). The study enrolled 602 chronic NSAID/acetaminophen users, aged ≥40 years with OA of the knee or hip. Patients received SoluMatrix diclofenac 35 mg b.i.d., which could be increased to t.i.d. and subsequently reduced to b.i.d. as needed. Safety assessments included AEs, vital signs, physical examination findings, 12-lead electrocardiogram, and clinical laboratory test results. Patient-reported outcomes were evaluated by the Short Form-36 (SF-36). RESULTS: A total of 601 patients received SoluMatrix diclofenac; 373 of 601 patients (62.1%) received treatment for ≥11 months. The most frequent AEs included upper respiratory tract infection, headache, urinary tract infection, diarrhea, nasopharyngitis, and nausea. Serious gastrointestinal, cardiovascular, renal, and hepatic AEs were uncommon. A small proportion (99 patients, 16.5%) of patients discontinued participation in the study due to AEs. Clinically meaningful improvements from baseline in Physical Component Summary Scores of the SF-36 were noted at week 12 and were sustained through week 52. Improvements in six of the eight individual physical and mental SF-36 domains were also noted. CONCLUSION: SoluMatrix diclofenac treatment for up to 1 year was generally well tolerated in patients with OA pain and associated with improvement in quality of life measures. TRIAL REGISTRATION: www.clinicaltrials.gov identifier: NCT01510912.