Abstract
PURPOSE: Since the launch of belimumab in 2011, the BLyS antibody has been increasingly used in the therapy of systemic Lupus erythematosus (SLE). Comparative studies showed that the intravenous (i.v.) and subcutaneous (s.c.) administration forms do not differ in their efficacy. Since the approval of the s.c. therapy, many patients have been switched from i.v. to s.c. administration. The clinical course of these patients and their satisfaction regarding the drug have not yet been investigated. METHODS: A total of 9 patients with SLE were switched from i.v. to s.c. belimumab between 12/2017 and 03/2018. We assessed a self-developed questionnaire on drug satisfaction, disease activity (SLEDAI-2k), serological activity (leukocytes, DNA antibodies, complement), disease damage (SLICC/ACR damage index) and functional status (health-assessment questionnaire) at switching (T0) and after 6 months (T1). Association of the questionnaires with the form of administration (i.v. vs s.c.) was analyzed for each variable separately by linear regression analyses, adjusted for age, gender and disease duration. RESULTS: At switching, disease activity of all patients was well controlled (median SLEDAI-2k = 2 [Interquartile range 0-4]) and the patients were mainly satisfied with their therapy. No evidence for any difference in disease activity, disease damage or patient satisfaction 6 months after switching was found. In tendency, patients were more satisfied with the s.c. administration. CONCLUSION: The switch from i.v. to s.c. belimumab was successful in all cases and had no effect on disease activity or patient satisfaction. Despite the small sample size, s.c. belimumab seems to offer a good alternative to i.v. application.