Tu1293 Soluble TNF Serum Levels During the Induction Phase in Crohn's Disease Patients With Anti-TNF Treatment

Letter: tumour necrosis factor alpha blocker switching – a not so simple pharmacokinetic. Authors' reply

“…However, in the Spanish multicenter PREDICROHN GETECCU study, we assessed the usefulness of measuring TNF serum levels to predict remission (at week 14) with anti-TNF treatment (either infliximab or adalimumab) in 117 patients with Crohn's disease. 4 TNF serum levels were measured using a highly sensitive modified ELISA, Collaborative enzyme enhanced reactive immunoassay (CEER), at baseline and at weeks 4, 8 and 14. We found that although, overall, basal TNF levels seemed to be lower among patients that reached remission under infliximab treatment, the concentration of soluble TNF was not useful for predicting response to the anti-TNF treatment during the induction phase.…”

“…2 It is postulated that these individuals may begin to associate certain GI symptoms with particular foods, leading to conditioned food aversions, and ultimately the development of disordered eating. [2][3][4][5] Yet, there is limited research in this area.…”

“…1 This could lead us to hypothesise that other factors and mechanisms may be involved in primary non-response -for example, high levels of TNF alpha at baseline. 3,4 In these cases, the second-line anti-TNF alpha shows a low remission rate (18%) in the first 2 months and only after additional administrations is it able to block the large amount of the cytokine in both serum and tissue to obtain remission. Consequently, we presume that the 70% of persistent non-responders are represented by the subgroup of patients whose inflammation is driven by other mediators and TNF alpha is irrelevant for the inflammatory process.…”