Comparison of clinical efficacy and safety of original and generic forms of etoricoxib in patients with knee osteoarthritis

Abstract

Background. Nonsteroidal anti-inflammatory drugs (NSAIDs) are an important drug class for the treatment of osteoarthritis (OA). Despite existing studies on the bioequivalence of original and generic NSAIDs, comparative studies related to their clinical efficacy and safety are limited. The purpose of the study was to compare the clinical efficacy and safety of the original and generic forms of etoricoxib in patients with knee OA. ­Materials and ­methods. In an open, comparative, randomized, multicenter study, 150 patients with knee OA were examined: group I — 50 persons who received the original etoricoxib (60 mg/d for 10 days), groups II and III — 50 subjects each who received generic etoricoxib (60 mg/d for 10 days). The effectiveness of the treatment was evaluated using the four-component visual analog scale (VAS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the Lequesne index before the start of therapy and on the 10th day. Assessment of tolerability and safety was studied by controlling adverse events based on clinical and laboratory indicators. Results. The use of the original and generic forms of etoricoxib in patients with knee OA led to positive dynamics of pain syndrome and functional activity, while the dynamics of indices were the greatest in the case of using the ori­ginal etoricoxib (VAS: group I — 50.0 [35.4–60.0] %, group II — 29.1 [16.7–55.0] % and III — 28.6 [14.3–33.3] %). The most pronounced positive dynamics of the pain syndrome against the background of taking the original etoricoxib compared to the generic forms was registered in the subgroup of patients with severe knee pain (VAS > 60 mm). The use of all forms of etorico­xib was safe and did not lead to serious clinical side effects or clinically signi­ficant changes in laboratory blood parameters. The hi­ghest rates of satisfaction with the treatment by patients and physicians were observed in the case of the original etoricoxib use. Conclusions. The use of the original etoricoxib in patients with knee OA, especially in the presence of severe pain syndrome (VAS > 60 mm) is the most justified and safe.