P577 Withdrawal of thiopurines in patients with Ulcerative Colitis in remission

Amor Costa, C.(1);Suárez Ferrer, C.(1);Poza Cordón, J.(1);Rueda García, J.L.(1);Sánchez Azofra, M.(1);Martín Arranz, E.(1);González Diaz, I.(1);Amiama Roig, C.(1);García Ramirez, L.(1);Martín Arranz, M.D.(1);

(1)Hospital La Paz Institute for Health Research - IdiPAZ La Paz University Hospital - Universidad Autónoma de Madrid, Gastroenterology and Hepatology, Madrid, Spain


Thiopurines (TP) are widely used in monotherapy in patients with ulcerative colitis (UC), mainly for the maintenance of remission in case of corticodependence or corticoresistance after cyclosporine use. However, these are drugs with significant side effects, especially in the long term.
The optimal duration of treatment with TP remains unknown, so it is important to determine the risk factors for relapse in order to identify the group of patients in which treatment can be withdrawn. 


A retrospective study was performed. Patients with UC in remission, in maintenance treatment with TP, who had discontinued the drug due to either maintained remission or the onset of adverse effects were included. 


26 patients were included, 1 with proctitis, 9 with left colitis and 16 with pancolitis. 24 (92.31%) were treated with azathioprine and 2 (7.69%) with mercaptopurine. The mean treatment time with TP was 68.09 months (standard deviation 56.65). 11 patients (42.31%) discontinued TP due to adverse effects and the remaining patients (57.69%) discontinued it by medical decision because they were in prolonged remission. After withdrawal of TP, 92.34% of patients continued treatment with mesalazine and the remaining 7.69% without concomitant treatment.

During follow-up, 10 patients (38.4%) relapsed and 16 patients (61.53%) had no relapse until the end of follow-up. The mean time from TP withdrawal to the onset of relapse was 69.15 months (standard deviation 52.53). Of the 10 patients who presented a flare, 5 (50%) were controlled by optimizing the dose of mesalazine, 4 (40%) required the addition of oral corticosteroids and 1 (10%) required biologics. 

No significant differences were found when comparing the time to relapse if the reason for discontinuation of TP was having had an adverse effect (65.05 months) or maintained remission (79.79 months) (p=0.42).  No statistically significant differences were found in time to relapse when comparing time on TP treatment, presence of concomitant treatment with mesalazine or active smoking. 


One third of patients relapsed after TP withdrawal. Discontinuation of TP in patients with UC in remission should be individualized according to the patient's risk factors, the indication and the duration of treatment.