Mucocutaneous disease activity in behçet's syndrome patients who discontinued colchicine treatment: An observational study

Background: Previous randomized controlled studies showed conflicting results regarding the effectiveness of colchicine on oral ulcers in Behçet syndrome (BS). A good trial design for the assessment of efficacy is randomized drug discontinuation. We aimed to assess mucocutaneous disease activity after 12 weeks in BS patients who discontinued colchicine. Methods: This single-center, single-blind, randomized controlled, open-label study included BS patients with mucocutaneous and joint involvement, and without major organ involvement. An independent observer blinded to group allocations performed assessments. At the end of a 12-week observational period where all patients continued to use colchicine, patients were randomized to continue or discontinue colchicine. Randomization was stratified according to sex, disease activity and duration. At the end of the 12-week controlled period, groups were compared for the number of oral ulcers, genital ulcers, erythema nodosum, swollen and tender joints, papulopustular lesions, pain of oral ulcers and genital ulcers, overall disease activity and life quality assessed using Behçet's disease current activity form (BDCAF) and Behçet's syndrome activity scale (BSAS), Behçet disease quality of life index (BDQoL) and SF-36V2. Primary endpoint was the mean number of oral ulcers at week 12. Results: The 141 patients were randomized to continue (70 patients, 45 F/25 M, age; 45±10 years, oral ulcers 1.1±1.3) or discontinue (71 patients, 46 F/25 M, age; 46±11 years, oral ulcers 1.04±1.0) colchicine. The number of oral ulcers at week-12 (2.7±2.6 vs 0.7±1.2, p<0.001), and area under the curve for oral ulcers over 12 weeks was higher (p<0.001). Conclusion: The significantly higher number of oral ulcers in patients who discontinued colchicine suggests that it may be effective for oral ulcers in some patients with BS.