P439 Stability of subcutaneous serum IFX (CTP13) levels between two injections and over two successive cycles in patients with Crohn's disease. (21st January 2022)

• Record Type: Journal Article
• Authors: Roblin, X; Bastide, L; Veyrard, P; Berger, A E; Paul, S
• Is Part Of: Journal of Crohn's and colitis. Volume 16(2022)Supplement 1
• Page Start: i421
• Page End: i422
• Publication Date: 2022-01-21
• Subjects: Inflammatory bowel diseases -- Periodicals; 616.344005
• DOI: 10.1093/ecco-jcc/jjab232.566
• Languages: English
• ISSNs: 1873-9946

Abstract

Abstract: Background: Under IFX sc, we do not know if there is a residual level of IFX. The aim of this work was to investigate this point by analyzing the intra-individual variability of the serum level of IFX sc. Methods: This was an observational, prospective study that included patients with CD undergoing maintenance treatment with IFX sc (120mg every, 14 days). Patients had IFX determinations (i Track, 10; Theradiag (France) at visit, 1 (day, 4 to, 6 after SC injection), visit, 2 (day, 7 to, 9 after sc injection) and visit, 3 (day, 13 to, 14 after sc injection) on two consecutive cycles. The first determinations were made only after, 8 weeks of switching from IV to SC. All patients at inclusion were in clinical remission (CDAI <, 150) with calprotectin levels <, 250 µg/g stool. Results: 20 patients (mean age:, 36 years, sex ratio M/F:, 1, mean duration of IFX IV:, 16 months) were included, i.e. meaning, 120 determinations., 8 patients were treated in combination with thiopurines. Mean residual levels before switch to sc were, 3.9 +/-1.2 µg/mL. Mean intraindividual levels between the two cycles were comparable (Visit, 1: cycle, 1:, 11.1 +/-, 4.4 µg/mL, cycle, 2:, 11.6 +/-, 4.6 µg/mL; p=0.65; Visit, 2: cycle, 1:, 12.0 +/-, 5.1 µg/mL, cycle, 2:, 11.3 +/-4.9 µg/mL; p=0.25; Visit, 3 cycle, 1:, 11.0 +/-4., 7 µg/mL, cycle, 2:, 10.9 +/-, 4.2 µg/mL; p=0.21. Serum IFX sc levels remained stable over the, 14 days between the two SC injections (p=0.36). Mean IFX levels at any dosing time were comparable in patients with and without thiopurines (IFX sc monotherapy: mean:, 11.5 +/-, 5.5 µg/mL versus IFX sc with thiopurines: mean:, 11.8 +/-, 4.6 µg/mL, p=0.54). Finally, residual IFX IV levels before switch did not influence the results of IFX sc serum concentrations (p=NS). Conclusion: Measure of IFX levels for IFX SC can be proposed at any time between two injections. No residual levels were found. These data are important for our clinical practice.