To investigate the switches performed in patients with rheumatoid arthritis under biological therapy and specifically comparing the switches from earlier days with more recent switches.
Patients with rheumatoid arthritis under biological therapy followed at Hospital Garcia de Orta, Almada, and included in the Rheumatic Diseases Portuguese Register (Reuma.Pt) were included in this study. Switches occurring before and after January 2007 were compared with respect to patients' demographic and clinical characteristics, such as disease activity and duration of biological therapy. The survival of the first biological agent was compared between patients starting biological therapy before and after 2007. EULAR response and remission rate at the last evaluation were calculated. Comparisons between groups were established using a t-test or chi--square, as appropriate. Survival curves of the first biological were compared through the logrank test.
In total, 123 patients were included in the analysis (mean age 57.0 ± 13.1 years and mean disease duration 11.7 ± 8.0 years). A total of 85 switches were documented, 20% of which took place before 2007. Comparing the switches before and after 2007, the latter were registered among older patients (recent switches 56.2 ± 12.9 years vs older switches 48.9 ± 11.0 years, p=0.04) and with a shorter duration of the first biological agent (recent switches 461.9 ± 293.2 days vs older switches 773.7 ± 475.8 days, p=0.03). No further significant differences were found, including the disease activity. The survival of the first biological was shorter in patients starting biological therapy after 2007 (2949 days for biological onset before 2007 and 818 days for onset after 2007, p <0.001). A good EULAR response was achieved by 19% and 30% of the patients, before and after 2007, respectively (p = 0.23). Remission was achieved by 14% and 22% of the patients, before and after 2007, respectively (p = 0.30).
Switches were more frequently performed in more recent years, in older patients and with a shorter duration of biological therapy. A trend towards a better and more targeted control of the disease could be discussed in light of our results. Although switches were more frequently performed in more recent years, in older patients and with a shorter duration of biological therapy, there is still room for improvement when aiming at remission, for example by applying a tighter therapy strategy like the "treat to target model".