['To compare the efficacy and safety of lumiracoxib with placebo and celecoxib for osteoarthritis OA in a 13 week, multicentre, randomised, double blind study.', 'After a 37 day washout period for nonsteroidal antiinflammatory drugs, 1702 patients with knee OA were randomised to lumiracoxib 200 or 400 mg once daily od, celecoxib 200 mg od, or placebo 2221. A visual analogue scale VAS pain intensity > or =40 mm was required. Primary efficacy variables were OA pain intensity VAS mm in the target knee, patients global assessment of disease activity VAS mm, and WOMAC pain subscale and total scores at 13 weeks. OA pain intensity, patients and physicians global assessment of disease activity, and WOMAC total and all subscale scores were analysed by visit as secondary variables.', 'Lumiracoxib showed significant improvements in all primary and secondary variables compared with placebo. Lumiracoxib 200 mg od and celecoxib 200 mg od achieved similar improvements in OA pain intensity and functional status. Lumiracoxib 400 mg od demonstrated better efficacy for OA pain intensity and patients global assessment of disease activity at weeks 2, 4, and 8 and similar efficacy at week 13 compared with celecoxib 200 mg od. The incidence of adverse events AEs, serious AEs, and discontinuations due to AEs was similar in each group.'] Is lumiracoxib effective in the treatment of osteoarthritis of the knee : a 13 week , randomised , double blind study versus placebo and celecoxib?