P695 Vedolizumab induction and maintenance though levels and long-term clinical and biochemical status in inflammatory bowel disease
A. Gutiérrez Casbas1, L. Sempere Robles2, R. Muñoz Pérez2, A. Rodríguez Angulo2, S. Climent3, J.I. Cameo Lorenzo2, M. Díaz3, P. Boada3, P. Más-Serrano3
1Department of Gastroenterology- CIBERehd, Hospital General Universitario Alicante, Alicante, Spain, 2Department of Gastroenterology, Hospital General Universitario Alicante, Alicante, Spain, 3Department of Pharmacy, Hospital General Universitario Alicante, Alicante, Spain
Background
Therapeutic drug monitoring (TDM) postinduction of vedolizumab (VDZ) could have relationship with long-term outcome of inflammatory bowel disease (IBD) patients. However, clinical utility of TDM during maintenance VDZ therapy remains unclear. To examine the association of induction and maintenance vedolizumab though levels (VTL) with clinical and biochemical long-term outcome in IBD patients.
Methods
We performed a retrospective cohort study, including all consecutive IBD patients of our centre on VDZ treatment who had VTL and anti-vedolizumab antibodies (AVA) measured during induction and maintenance therapy. All patients had received a minimum of 6 weeks therapy following standard induction (0, 2, 6 ± 10 week dosing. Clinical response and remission were defined by Partial Mayo Score (PMS, UC) or Harvey Bradshaw Index (HBI, CD) and were assessed at week 52.Biochemical remission was defined as CRP < 0.5 g/dl and faecal biomarker remission as faecal calprotectin (FC) < 250 µg/g. Measurement of VTL and AVA was performed by ELISA assays(Vedolizumab-TheraDiag(R) with a detection limit for VTL of 2 μg/ml and measurement range of 2–60 μg/ml.
Results
In total, 34 patients were included (55.9% UC; 44.1% CD, 50% women). Median age was 52.76(17–83) and mean disease duration was 8 ± 7.2 years. Median baseline HBI was 6(0–12) and PMS was 5(3–7). FC and CRP measured before first dose of VDZ were 1425 ± 1189 μg/g and 2.1 ± 2.4 mg/dl. A total of 14 patients (41.2%) were naïve for biologic therapy. Only three patients (8.8%) were receiving a concomitant immunomodulator. Clinical response to induction phase was reported in 76%. Clinical remission, clinical response, biochemical remission and faecal biomarker remission were present in 30% (9/29), 41.4% (12/29), 40.9% (9/22) and 35% (7/20), respectively, at week 52. Thirteen patients (13/26, 50%) needed dose escalation at week 52. Twenty-six patients (78.8%) were persistent in VDZ therapy at the end of the study. The median level of VDZ at weeks 6 and 24 were 16.13 ± 7.06 μg/ml and 9.6 ± 6.7 μg/ml. Comparing patients with and without clinical response or remission to VDZ at week 52 no significant difference in VTL was found at Week 6 (16.27 vs. 15.46 μg/ml,
Conclusion
In this real-world study of IBD patients receiving VDZ, early induction or maintenance VTL are not associated with long-term outcome.