Early haematologic response to anifrolumab in systemic lupus erythematosus: results from the european multicentre EFFORT-SLE study.

Abstract

To evaluate the efficacy and safety of anifrolumab (ANI) for the hematologic manifestations of systemic lupus erythematosus (SLE) in routine clinical practice. In this retrospective multicentre European study, adult patients with SLE presenting ≥1 disease-related hematologic abnormality at ANI initiation were included. Clinical and laboratory data were collected at baseline and at 3, 6, 12, 18 and 24 months. Complete hematologic response (CHR) was defined as normalisation of all baseline abnormalities, whereas partial hematologic response (PHR) as normalisation of at least one affected lineage. Forty-seven patients from seven European countries were included (91.5% female). ANI was specifically initiated for hematologic involvement in 21/47 (44.7%), whereas 26/47 (55.3%) started treatment for other SLE manifestations but had ≥1 hematologic abnormality at baseline. CHR was achieved in 8/43 (18.6%) patients at 3 months and cumulatively in 14/46 (30.4%) within 6 months (overall 17/47, 36.2%), with comparable rates regardless of treatment indication. PHR occurred in 17/43 (39.5%) at 3 months and 11/37 (29.7%) at 6 months. Haemoglobin, leukocyte and lymphocyte counts significantly improved by month 3, whereas platelet counts showed a non-significant increase. Higher baseline CRP, ESR and SLE-DAS were associated with lack of CHR. Twelve patients (25.5%) discontinued ANI and 17 (36.2%) experienced adverse events without discontinuation. ANI was associated with early hematologic improvement, with one-third of patients achieving complete normalization under a stringent definition of remission. Responses involved multiple hematologic lineages and were less frequent in patients with higher inflammatory activity, although confirmation in broader populations is warranted.