P400 Evolution of clinical and pharmacological parameters after switching from intra-venous to subcutaneous infliximab in patients with inflammatory bowel disease: the REMSWITCH study
Buisson, A.(1);Nachury, M.(2);Reymond, M.(1);Yzet, C.(3);Wils, P.(2);Payen, L.(1);Manlay, L.(1);Pereira, B.(4);Fumery, M.(3);
(1)University Hospital Estaing, Department of Gastroenterology- IBD Unit, Clermont-Ferrand, France;(2)CHRU Lille, IBD Unit, Lille, France;(3)CHU Amiens, IBD Unit, Amiens, France;(4)CHU Clermont-Ferrand, DRCI Biostatistics Unit, Clermont-Ferrand, France;
Background
Owing to similar efficacy, switching from intravenous (IV) to subcutaneous (SC) infliximab (IFX) is an attractive option, but the feasibility of switching patients with intensified IFX therapy remains unknown.
We assessed the clinical and pharmacological evolution after switching from IV to SC IFX in IBD patients to evaluate the feasibility and to determine the equivalence between IV and SC doses.
Methods
All IBD patients in clinical remission (CDAI < 150 or partial Mayo score ≤ 2) were consecutively included in 3 IBD centers and were switched to SC IFX 120mg/2 weeks (wk) (regardless of IV dose) at the theoretical day of IV infusion (visit 0 = V0) and were followed every 4 to 8 weeks according to the initial IV regimen for 6 months.
Results
Among 246 screened patients, 65 (26.4%) were not eligible (no clinical remission or physician’s decision), and 71.8% (130/181) accepted to switch to SC IFX (Crohn’s disease = 73,1%, concomitant immunosuppressant = 25.4%, median faecal calprotectin = 35 µg/g [16-104]). 43.1% of the 130 patients received 5mg/kg/8 wk.
In 130 patients, clinical relapse leading to therapeutic escalation was observed in 11.1% including 4.0%, 8.6%, 11.1% and 40.0% in patients treated with 5mg/kg/8wk, 10 mg/kg/8wk, 10mg/kg/6 wk and 10mg/kg/4 wk, respectively. Dose increase (240 mg/2 wk) induced clinical remission in 92.3% of relapsers.
Infliximab trough levels (TL) were significantly higher after switching from IV to SC IFX: 9.8 ±6.4 vs 14.4 ±5.7 (p<0.0001). TL increased in patients receiving 5 mg/kg/8 wk (6.3 ± 3.4 vs 14.7 ±5.7; p<0.0001) or 10 mg/kg/8 wk (8.4 ±5.6 vs 13.7 ±6.6; p=0.001) but remained stable in those treated with 10 mg/kg/6 wk (11.1 ±7.6 vs 13.1 ±5.1; p=0.31) or 10 mg/kg/4 wk (17.8 ±4.2 vs 15.8 ±4.6; p=0.12) (Figure 1).
.
Infliximab TL remained stable (variation V1-V0 < ± 1) in 4.3%, 15.0 %, 33.3 % and 50.0 % of the patients with the following IV doses: 5 mg/kg/8 wk, 10 mg/kg/8 wk, 10 mg/kg/6 wk and 10 mg/kg/4 wk, respectively (p=0.003). No patient developed anti-IFX antibodies.
TL before the switch (8.4 ±5.6 for non-relapsers vs 12.0 ±7.2 for relapsers; p=0.12) and TL after the switch (14.5 ±5.6 vs 13.6 ±5.6; p=0.63) were not significantly associated with the risk of relapse. In contrast, the risk of relapse was higher in patients with stable or decreasing TL after the switch compared to those with increased TL (31.8% vs 7.1%; p=0.024). The type of IBD and concomitant immunosuppressant were not associated with the risk of relapse. Patients’ acceptability was better with SC injections compared to IV infusions (10pts-acceptability numerical scale = 8.7 ±1.6 vs 6.8 ±0.9; p<0.0001).
Conclusion
Switching from IV to SC IFX is feasible and well-accepted leading to a low risk of relapse in patients with IBD.