Diclofenac and piroxicam in a double-blind trial results and methodological problems. Working Party of the Society for Rheumatology of the GDR for the Testing of Anti-rheumatic Drugs.
Diclofenac (150 mg/d) and piroxicam (20 mg/d) were compared in a cross-over trial with 12-day periods of double-blind treatment and 3-day wash-out periods. The following open phase of the trial lasted for two months and served to assess the tolerance. For this the dosage of diclofenac was reduced to 100 mg/d. 134 volunteers from 5 departments of rheumatology participated in the study. Statistical analysis showed that the two groups were of homogenous composition and that--with certain limitations--the necessary assumptions for the evaluation as a cross-over experiment were fulfilled. All tests used to determine the efficacy showed approximately parallel improvement with both formulations and in the wash-out phase this was followed by marked deterioration. The sum of the parameters for individual improvement showed a tendency in favour of piroxicam. However, clear superiority of one trial formulation over the other with respect to efficacy or tolerance could not be demonstrated by the statistical analysis.
D000328:Adult; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D002986:Clinical Trials as Topic; D004008:Diclofenac / Q000009:adverse effects / Q000627:therapeutic use*; D004311:Double-Blind Method; D004361:Drug Tolerance; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010894:Piroxicam / Q000009:adverse effects / Q000627:therapeutic use*
D010894:Piroxicam; D004008:Diclofenac