To evaluate reported information on prednisone therapy in the main studies of biological agents used to treat rheumatoid arthritis (RA).
We reviewed 66 publications (including four abstracts), including 11 studies of infliximab, 19 of etanercept, eight of adalimumab, five of golimumab, four of certolizumab, four of rituximab, eight of abatacept, and seven of tocilizumab.
Whether concomitant prednisone therapy was used, it was specified in only 56 (85%) of the 66 publications. Only 42 (64%) publications indicated that the prednisone dosage remained unchanged throughout the study. The maximum prednisone dosage allowed was specified in only 39 (59%) reports and was lower than 8 mg/day in only four (6%) studies. Data enabling determination of the mean daily prednisone dosage in prednisone-treated patients was available for only eight (12%) studies; the mean dosage ranged from 5.0 to 9 mg/day (mean, 7.1 ± 1.5). The percentage of patients receiving prednisone therapy was reported for only 41 (62%) studies. All the above-mentioned information was available in only two (3%) study reports. The percentage of patients on prednisone therapy ranged from 34% to 93% (mean, 58 ± 13%) overall and varied across biological agents as follows: abatacept, 74.4%; golimumab, 67.9%; infliximab, 60.6%; certolizumab, 57.5%; rituximab, 57.5%; etanercept, 54.4%; tocilizumab, 52.8%; and adalimumab, 50.4%. These percentages did not decline between 1997 and 2010.
Study reports provide inadequate information on prednisone therapy during biological treatment for RA.