To evaluate 4-year retention rates of tumor necrosis factor-α (TNF-α) inhibitors adalimumab, etanercept, and infliximab among patients with longstanding rheumatoid arthritis (RA), as derived from an Italian national registry.
The clinical records of 853 adult patients with RA in the GISEA (Gruppo Italiano Studio Early Arthritis) registry were prospectively analyzed to compare drug survival rates and the baseline factors that may predict adherence to therapy.
In 2003 and 2004, 324 patients started treatment with adalimumab, 311 with etanercept, and 218 with infliximab. After 4 years, the global retention rate of anti-TNF-α therapy was 42%. Etanercept survival (51.4%) was significantly better than that of infliximab (37.6%) or adalimumab (36.4%; p < 0.0001). Accordingly, the mean duration of therapy was significantly longer for etanercept (3.1 ± 2 yrs) than for adalimumab (2.6 ± 2 yrs) or infliximab (2.7 ± 2 yrs; p < 0.05). The use of concomitant disease-modifying antirheumatic drugs, mainly methotrexate, and the presence of comorbidities significantly predicted drug continuation (p < 0.01), whereas a high Disease Activity Score did not.
The 4-year global drug survival of adalimumab, etanercept, and infliximab was lower than 50%, with etanercept having the best retention rate. The main positive predictor of adherence to anti-TNF-α therapy was the concomitant use of methotrexate. Our study provides further evidence that the real-life treatment of patients with RA may be different from that of randomized clinical trials.