• Ali Eqbal, Alicia Martin, James D Doecke, and Desmond Patrick.
• Department of Gastroenterology and Hepatology, Sunshine Coast University Public Hospital, Sunshine Coast, Queensland, Australia.
• Intern Med J. 2023 Apr 1; 53 (4): 559567559-567.

BackgroundThioguanine is an alternative thiopurine for inflammatory bowel disease (IBD) patients.AimsTo evaluate the short-term efficacy and safety of low-dose therapeutic drug-monitored (TDM) thioguanine.MethodsA retrospective evaluation of IBD patients intolerant to conventional thiopurines started on thioguanine from 2017 to 2019 with dosing guided by TDM was conducted. Clinical response was defined for ulcerative colitis (UC) as a reduction of partial Mayo score ≥3 with reduction in rectal bleeding score of at least 1 and a final rectal bleeding subscore of 0-1 at Week 12 of therapy. Crohn disease (CD) response was defined as a reduction of Harvey-Bradshaw index ≥3 (HBI) at Week 12 of therapy. Remission was defined in UC as partial Mayo score of <2 and in CD as HBI score of <5.ResultsForty-six patients were included in the study. The median thioguanine dose was 20 mg/day (standard deviation 7.3; range: 10-40 mg/day) with a median 6-thioguanine nucleotide level of 577 pmol/8 × 108 (interquartile range (IQR) IQR 378.5-878.75) for CD and 677.5 pmol/8 × 108 (IQR 523.25-842.25) for UC. The overall clinical response rate was 62% (13/21), intention to treat (ITT). Maintenance of remission was 76% (19/25, ITT). Thirty-seven percent (17/46) of patients experienced an adverse effect. No early cases of nodular regenerative hyperplasia (NRH) were seen.ConclusionThioguanine was tolerated well in 63% of patients. A clinical response was seen in 62% of patients, and maintenance of remission was high at 76%. No cases of early NRH were seen. Longer-term follow up is required to ensure safety and to assess durability of response.© 2021 Royal Australasian College of Physicians.

16 keywords...

hide…