Patients with rheumatoid arthritis (RA) may discontinue the use of tumor necrosis factor (TNF) inhibitors if they feel a loss or lack of treatment efficacy. They may also discontinue use due to adverse events. A recent analysis of RA patients found that more patients who received etanercept remained on the treatment after 12 months than those who received other TNF inhibitors. The Journal of Rheumatology published the systematic literature review by Paul Emery, MA, MD, Arthritis Research U.K. professor of rheumatology and head of Leeds Institute of Rheumatic and Musculoskeletal Medicine at the University of Leeds and colleagues online June 1, 2019.1
The initial research yielded a total of 4,412 publications. However, the final analysis included 133 full publications and 37 conference abstracts for a total of 270,000 RA patients. Fourteen of 170 publications had overlapping patient data from six data sources. The studies’ documented mean or median follow-up time ranged from 12 months to 12 years. There was some inconsistency regarding reports on mean and median at baseline 28-joint Disease Activity Score (DAS28), as well as presentation for overall scores for all treatments vs. scores separated according to specific TNF inhibitor.
The researchers found treatment with etanercept was associated with the highest rate of drug survival among the five TNF interferon inhibitors currently used to treat RA. The authors define drug survival as the proportion of patients still receiving treatment at a certain timepoint and evaluated patient retention, persistence and continuation. They note that there were very little data on certolizumab pegol and golimumab, which appeared in only two of the 170 publications and abstracts. In the first-line setting, drug survival rate at 12 months was 71% for etanercept, 69% for infliximab and 70% for adalimumab. At 12–24 months, the survival rate was 63% for etanercept, 57% for infliximab and 59% for adalimumab. In the second-line setting, the drug survival rate at 12 months was 61% for etanercept, 69% for infliximab and 55% for adalimumab. At 12–24 months, it was 53% for etanercept, 39% for infliximab and 43% for adalimumab.
When the authors excluded publications that did not separate data into specific treatment types, they found that, when they analyzed drug survival rate greater than 36 months, it was 59% for etanercept, 49% for infliximab and 51% for adalimumab in the first-line setting. In the second-line setting, the rates were 56%, 48% and 41%, respectively. The discontinuation rate at 36 months of follow-up was 38–48% for etanercept, 42–62% for infliximab and 38–59% for adalimumab. When researchers looked at discontinuation due to adverse events at 36 months of follow-up, they found patients receiving etanercept had the lowest rates of discontinuation (8–16%) followed by patients receiving adalimumab (8–26%) and patients receiving infliximab (15–27%).