IMPACT OF TREATMENT RESPONSE WITH ADALIMUMAB ON RISK OF SERIOUS INFECTIONS IN PATIENTS WITH CROHN’S DISEASE: SECONDARY ANALYSIS OF THE PYRAMID REGISTRY

Abstract

Abstract BACKGROUND AND AIMS Treatment efficacy and safety are primary factors in choosing therapies in patients with Crohn’s disease (CD). However, they can be perceived to be at odds with each other with more potent therapies associated with increased risk of infections. We evaluated the impact of treatment response on the risk of serious infections in adalimumab-treated patients with CD through secondary analysis of the PYRAMID registry. METHODS We included patients with CD who newly started adalimumab in the prospective PYRAMID registry (NCT00524537) and classified them as treatment responders (achieved steroid-free clinical remission based on patient-reported outcomes) vs. non-responders (not in steroid-free clinical remission) at 6m after treatment initiation (landmark). We compared the risk of serious infections between responders vs. non-responders between 6-36m after treatment initiation, through stabilized inverse probability of treatment weighted (IPW) Cox proportional hazards model. RESULTS Of 1515 adalimumab-treated patients with complete data at 6m, 763 (50.4%) were classified as responders (37±13y, 56% female, disease duration, 9.5y). At time of starting adalimumab (baseline), as compared with non-responders, responders were less likely to have moderate to severe symptoms (55.6% vs. 33%), require steroids (45.5% vs. 17.3%) or opiates (6.6% vs. 1.3%), have had prior CD-related surgery (46.5% vs. 35.1%), without any differences in disease location, perianal disease, and prior CD complications. On follow-up, between 6-36m (observation period after 6m landmark), 123 patients experienced a total of 162 serious infections. Of these, 52 responders (6.8%) experienced a serious infection vs. 71 non-responders (9.4%). Approximately, 58% infections were classified as gastrointestinal in origin. On stabilized IPTW through generalized boosting model, responders were 34% less likely to experience serious infections on follow-up compared with non-responders (HR, 0.66; 95% CI, 0.46-0.96). There was no significant difference in risk of serious infections between responders vs. non-responders based on organ site (gastrointestinal infections: HR, 0.61; 95% CI, 0.38-0.99; extra-intestinal infections: HR, 0.61; 95% CI, 0.46-1.30) (p-value for difference in groups = 1.00). Responders were significantly less likely to require corticosteroids on follow-up (1y: 4.4%, 2y: 8.9%, 3y: 9.6%), compared with non-responders (1y: 50.7%, 2y: 51.6% vs. 3y: 51%). CONCLUSIONS Patients with CD who respond to adalimumab have lower risk of developing serious infections, compared with non-responders, after accounting for disease severity. These findings underscore that initiation of advanced therapy for CD may lower the risk of serious infections through effective disease control and avoidance of corticosteroids.