Successful intra-class switching among IL-17 antagonists: a multicentre, multinational, retrospective study.

IL-17 blockers are among the newer anti-psoriatic treatment options and little is known about the interclass switching. We have thus initiated a multi-center, multi-national, retrospective study to assess the treatment response of patients who were switched from one IL-17 blocker to another. Analysis consisted of data from patients with moderate-to-severe psoriasis who did not respond satisfactorily to one of the available IL-17 blockers (secukinumab, ixekizumab, brodalumab) and were subsequently switched to another drug of this class. After 12 weeks of treatment, patients' PASIs were evaluated. Treatment success was defined as reaching PASI 75 after 12 weeks. Topical treatment was allowed and used in all patients. 26 patients were included (13 male, 13 female) and 29 switches were evaluated. Overall, 29 switches in 21 patients were evaluated. 18 patients changed their therapy from secukinumab to ixekizumab, or in 7 cases to brodalumab. Brodalumab was used in 3 cases after failure of treatment with ixekizumab. Only in one case, non-response of brodalumab resulted in a therapy switch to secukinumab. In 15 (52%) cases, PASI 75 was reached. In 6 (20%) patients, the switch led to a PASI 50 response. No success of treatment was seen among 8 (28%) participants. When patients fail to respond or do not tolerate an IL-17 blocker, switching to another anti-IL-17A/RA is a promising viable option. Larger studies are needed to confirm our results.