Diclofenac topical solution compared with oral diclofenac: a pooled safety analysis

Area of Science:

• Pharmacology
• Rheumatology
• Clinical Trials

Background:

• Topical nonsteroidal anti-inflammatory drug (NSAID) formulations offer localized treatment for osteoarthritis (OA) with reduced systemic exposure.
• The comparative safety and efficacy of topical NSAIDs versus oral formulations remain a subject of ongoing research and debate.

Purpose of the Study:

• To compare the safety and efficacy profiles of diclofenac topical solution (TDiclo) versus oral diclofenac (ODiclo) in patients with symptomatic knee osteoarthritis.
• To evaluate adverse events, vital signs, dermatologic responses, and clinical laboratory parameters in a pooled safety analysis.

Main Methods:

• Two 12-week, double-blind, randomized, controlled, multicenter studies were conducted.
• A pooled safety analysis included 927 patients with radiologically confirmed symptomatic knee OA, comparing TDiclo (45.5% dimethyl sulfoxide) with ODiclo.

Main Results:

• Adverse events (AEs) were reported in 67.1% of TDiclo users versus 64.5% of ODiclo users.
• TDiclo showed a higher incidence of dry skin at the application site but significantly fewer gastrointestinal and cardiovascular AEs compared to ODiclo.
• ODiclo was associated with greater adverse changes in liver enzymes, creatinine, creatinine clearance, and hemoglobin.

Conclusions:

• Diclofenac topical solution (TDiclo) is an effective treatment for osteoarthritis (OA).
• TDiclo presents a more favorable safety profile than oral diclofenac (ODiclo), suggesting it as a useful alternative NSAID therapy.