LONDON — Switching from tumour necrosis factor-α inhibitors adalimumab to etanercept, or vice versa, after an unsatisfactory treatment response can result in an improved treatment outcome, Austrian researchers have found. However, their results also showed that patients who restarted adalimumab after a treatment interruption experienced a weaker treatment response.
Over time many patients treated with TNF-α inhibitors stop taking them, often because they don’t respond initially, the response wanes, they experience an adverse event, choose to stop, switch to another biologic, or undergo complete remission.
To explore how patients would respond if they restarted the same or a different TNF-α inhibitor, the researchers downloaded data from the Austrian Psoriasis Registry (PsoRA), which contains details of 3400 psoriasis patients. A total of 141 patients met the inclusion criteria for this analysis, which meant they had been treated with a TNF-α inhibitor for 3 months or longer, but then switched to another TNF-α inhibitor or restarted on the same drug after an interruption of at least 3 months. The TNF-α inhibitors taken were inï¬iximab (IFX), adalimumab (ADA) and etanercept (ETA), but there was insufficient data to analyse patients’ use of inï¬iximab treatment (fewer than 10 patients in each group).
Patients switching from etanercept to adalimumab made up the largest group (72 patients), while there were 20 patients who switched from adalimumab to etanercept, and each drug was stopped and restarted in 12 patients. The main reason for switching drugs was treatment failure, whereas treatment interruptions were mainly due to patients deciding to stop treatment or complete remission.
Analysis of the data showed that when patients switched from one TNF-α inhibitor to another they experienced some improvement. Patients switching from etanercept to adalimumab experienced a 0.97 reduction in PASI score (from 4.49 to 3.51; P < 0.001), while those who switched from adalimumab to etanercept experienced a fall of 1.05 (from 4.10 to 3.05; P = 0.035). Treatment response was sustained in patients who restarted etanercept after a break (2.75 vs. 2.75, P = 1.0), but was lower in patients who restarted adalimumab in whom PASI score actually increased by 1.08 (from 1.58 to 2.67; P = 0.055).
Presenting the findings to the Psoriasis: From Gene to Clinic International Congress in London on Dec. 2, Dr. Peter Wolf of the Medical University of Graz in Austria said: “These data generated under daily-life conditions are consistent with the notion that after an initial unsatisfactory treatment response, switching either from ETA to ADA or from ADA to ETA can result in an improved treatment outcome. Moreover, the data also support the concern that after treatment interruption, restarting with ADA (presumably due to neutralizing antibodies) but not with ETA may result in a weaker treatment response.”
For the patients who used adalimumab (ADA) and/or etanercept (ETA), the median length of the first cycle of treatment was just over 10 months. The median PASI at the end of the first cycle was 10.2 in patients who switched from etanercept and 1.15 in those with interrupted treatment, while for adalimumab the median PASI achieved by patients who had switched and interrupted treatment was 16.7 and 1.4 respectively. For both drugs the median length of treatment interruption was approximately 10 months, and the median length of the second treatment cycle around 20 months.
P. Wolf, W. Weger, L. Richter, et al. “Switching or restarting of tumour necrosis factor-α inhibitors after interruption under daily-life conditions: efï¬cacy report from the Austrian Psoriasis Registry (PsoRA),” From Gene to Clinic International Congress, London , Dec. 2, 2017, 12.25. http://psoriasisg2c.com/wp-content/uploads/2017/11/Online-Psoriasis-G2C-Programme-2017.pdf (page 71)