P923 Haematological abnormalities during treatment with Janus kinase inhibitors in patients with Ulcerative Colitis: a post hoc analysis

Abstract

Abstract Background Janus kinase inhibitors (JAKi) are used for Ulcerative Colitis treatment and could lead to haematological abnormalities, such as anaemia. In this post hoc analysis, we evaluated whether treatment with tofacitinib or filgotinib is associated with anaemia and other haematological laboratory abnormalities. Methods Data from randomized clinical trials [OCATVE 1 (NCT01465763), OCTAVE 2 (NCT01458951), OCTAVE Sustain (NCT01458574), and summary-level data from SELECTION (NCT02914522)] evaluating the efficacy of filgotinib and tofacitinib were used in this post hoc analysis. Adult patients with moderate-to-severe Ulcerative Colitis received induction therapy with filgotinib, tofacitinib, or placebo. After induction, patients in remission were re-randomized to receive either filgotinib 100 mg QD, filgotinib 200 mg QD, tofacitinib 5 mg BID, tofacitinib 10 mg BID, or placebo. We evaluated and compared the proportions of patients with anaemia, leukopenia, neutropenia, lymphopenia, and thrombocytopenia at baseline, after induction therapy (i.e., 8–10 weeks), and after 52–58 weeks of maintenance therapy in these treatment groups. Results At least a third of patients across all treatment groups had anaemia at baseline, the proportion of those who recovered from anaemia after induction did not differ (Table 1): 29.9% in the tofacitinib 10 mg group, 25.6% in the filgotinib 200 mg, and 30.7% in the filgotinib 100 mg group (P = 0.571). The proportion of patients who developed anaemia after the induction phase also did not differ: 16.7% in the tofacitinib 10 mg group, 17.3% in the filgotinib 200 mg, and 12.1% in the filgotinib 100 mg group (P = 0.880), as presented in Table 1. In contrast, 3.1–5.6% of patients in the tofacitinib groups vs. 7.1–14.5% in the filgotinib groups developed anaemia after 52–58 weeks of treatment (P = 0.036); however, the difference was not statistically significant after correction for multiple testing. Other haematological laboratory abnormalities, except lymphopenia, either did not occur or occurred infrequently across all treatment groups. Data regarding lymphopenia was available only from the OCTAVE trials; after 52 weeks of maintenance therapy, approximately 22% of patients in the tofacitinib groups had lymphopenia compared with 3.8% in the placebo group (P = 0.008). Conclusion Heterogeneous data limited this post hoc analysis. Haematological laboratory abnormalities, except for anaemia and lymphopenia, were infrequent. Therapy with JAKi was not associated with an increased occurrence of anaemia. However, since lymphopenia occurred more frequently in patients under treatment with tofacitinib, close monitoring is advisable to manage the risk of infection in these patients.