Introduction Anti-Tumour Necrosis Factor alpha antibodies (anti-TNFs) are widely used for the treatment of severe and fistulising Crohn’s Disease (CD). They are, however, associated with a number of adverse events (AEs) including infections, neutropenia, malignancy, demyelinating disease and infusion reactions. We aimed to evaluate the safety profiles Adalimumab (Al) and Infliximab (Ifx) amongst patients with CD at Central Manchester University Hospitals.

Methods 217 CD pts were identified retrospectively from our anti-TNF database; data was retrieved from clinic letters. A probit regression was used to correlate AEs and pt characteristics.

Results Median age of pts was 41 (range 20–79) yrs. Total lifetime yrs on anti-TNFs was 740.6 (331.2 on Ifx, 409.4 on Al) yrs. 133 pts were treated with Ifx (75 females), 4 had previously been on Al. Median length of Rx with Ifx was 20 (range 1 dose-still on at 140) months. 98 (73.6%) pts on Ifx were on a concomitant immunomodulator drug. 141 pts were treated with Al (79 females), 53 had previously been on Ifx. Median length of Rx with Al was 33 (range <1-still on at 89) months. 62 (44.0%) pts on Al were on a concomitant immunomodulator.

54 (40.6%) pts had AEs whilst on Ifx (see Table 1 for severity), including lymphoma (2 pts), solid organ tumours (3), pulmonary TB (2), infusion reaction (13), cutaneous side effects (SEs) (7), other infections (12). 33 pts were still on Ifx at the time of this study. 30 pts (22.6%) stopped Ifx due to AEs. 13 pts had an infusion reaction. Pts were most likely to have an infusion reaction at infusion 2 (6 pts).

Overall, 57 (39.7%) pts suffered from AEs on Al (see Table 1 for severity), including solid organ tumours (2 pts), cutaneous SEs (10), neurological symptoms (3) and other viral/bacterial infections (28). 88 pts were still on Al at the time of this study. 21 pts (14.9%) stopped Al due to AEs.

Pts were more likely to suffer from an AE with increasing age (p = 0.041 for Ifx, p = 0.016 for Al). Patients over 50 yrs were more likely to suffer from an AE than those less than 50 (p = 0.015 for Ifx, p = 0.015 for Al). Pts over 70 yrs were more likely to suffer from a moderate or severe AE on Al (p = 0.009), there was no relationship for Ifx. Gender, smoking status and use of immunomodulators had no effect on AEs. No significant relationship found between length of Rx and development of AEs. No statistically significant difference found in AEs frequency between Ifx and Al.

Conclusion This study found that AEs are independent of the length of time on anti-TNFs, but are associated with increasing age of the patient. Patients over 50 yrs are more likely to have an AE on Ifx and Al. Patients over 70 yrs are more likely to have a moderate or severe AE on Al.

Disclosure of Interest None Declared.