Trough levels and antibodies to infliximab may not predict response to intensification of infliximab therapy in patients with inflammatory bowel disease
Inflammatory Bowel Disease, 04/16/2012
Pariente B et al. – In patients with inflammatory bowel disease (IBD) who lose response to infliximab, clinical improvement may occur upon intensification of infliximab therapy, irrespective of infliximab serum concentration or presence of antibodies to infliximab (ATI).Methods
- The authors retrospectively studied records of IBD patients who lost response to infliximab therapy.
- They first assessed clinical responses of different therapeutic strategies that were applied when patients lost response to infliximab and then they looked at the correlation between clinical response and infliximab trough levels and ATI concentrations.
- Seventy-six IBD patients were included.
- 31/76 patients (41%) continued infliximab therapy without any modification, 39 patients (51%) had an intensification of infliximab therapy, five patients (7%) had switched to adalimumab therapy, and one patient (1%) underwent surgery.
- Clinical response was observed in 27 patients (69%) with an intensification of infliximab therapy.
- There was no significant difference in mean infliximab trough level at inclusion in patients who responded to intensification of infliximab therapy (3.3 ± 4.1 μg/mL) as compared with patients who did not respond (2.3 ± 2.2 μg/mL, P = 0.85).
- In all, 16/76 patients (22.4%) presented detectable ATI in the serum.
- Ten ATI-positive patients had an intensification of infliximab therapy and six (60%) demonstrated a clinical response.
- After intensification of infliximab therapy the ATI concentration decreased in five patients.