P254 Factors that may predict the need for infliximab optimization in Crohn's disease

Flores, C.(1);Petry, R.(2);Bortolin Fonseca, C.(2);Dos Santos Harlacher, L.(1);

(1)Instituto do Aparelho Digestivo, Crohn's and Colitis Reference Center, Porto Alegre, Brazil;(2)Universidade Federal do Rio Grande do Sul, Post-graduation in gastroenterology and hepatology, Porto Alegre, Brazil


Biological therapy has revolutionized treatment of Crohn’s Disease (CD), increasing the rate of disease remission. Despite this, a significant percentage of patients present partial response or loss of response over time. These patients need optimization of therapy, whether by increasing the dosage or reducing the interval between infusions. The main objective of this study was to identify possible factors related to the need to optimize the dose of infliximab (IFX) in patients with CD. This finding can facilitate the early identification of the need for therapeutic optimization, reducing the risks of unfavorable evolution and decreasing costs related to the disease.


Retrospective and prospective maintained database of CD patients under IFX treatment being followed up in the Infusion Center at the Day Hospital of the Hospital de Clínicas de Porto Alegre, Brazil, from 2009 to 2018. Epidemiological, clinical, laboratory and endoscopic characteristics that correlate with worse prognosis of CD were evaluated. The main goal of the study was to identify possible factors related to the need for (IFX) optimization.


121 patients were evaluatedOf these, 58 (47,93%) needed the optimization of the IFX dosage. The only variables that had significant statistical difference between the groups with or without need for optimization were anemia (p=0.019) and C reactive protein (CRP) which were persistently elevated in week 14 (p=0.039). After the adjustment with the multivariate model, only the elevated CRP during week 14 was still statistically significant, with a 119% greater risk of optimizing treatment when compared to those of normal CRP.

Figure 1 - Cumulative IFX optimization (%)

Time (years) Opmization (%)
1 16.6
2 34.3
3 40.5
5 46.6
10 53.9


Among the factors studied, only the maintenance of higher CRP during week 14 was associated to the need for optimization of the IFX dose. This finding agrees with the literature that describes week 14 as an ideal moment for evaluating the serum levels of immunobiologics as a predictor of sustained response. Thus, in the absence of therapeutic drug monitoring, we could look at persistently high CRP as a marker of the need for therapeutic optimization. This finding needs to be confirmed in prospective studies.