Targeting type I interferon in lupus autoimmune haemolytic anaemia: first report with anifrolumab.

OBJECTIVE

Autoimmune haemolytic anaemia (AIHA) occurs in approximately 5-10% of patients with SLE and it is traditionally associated with higher disease activity, increased damage accrual and reduced survival. SLE management recommendations partially address disease-related haematological manifestations without specific indication for AIHA treatment. Indeed, therapeutic approaches are prevalently extrapolated from the haematology field. In the present report, we aimed at describing a case series of patients with SLE and AIHA successfully treated with anifrolumab (ANF).

METHODS

We described patients with SLE treated by ANF with active AIHA at the drug initiation. Clinical and laboratory data were reported in a standardised electronic form, including laboratory evidence of haemolysis. Overall disease activity was assessed by using the SLE Disease Activity Index 2000 (SLEDAI-2k). We collected patients data at baseline (T0), after 1 month (T1) and every 3 months thereafter.

RESULTS

We included seven patients (6F/1M, median age 61 years (IQR 33), median disease duration 48 months (IQR 72)). All the patients had a positive direct Coombs test and laboratory evidence of active haemolysis at ANF starting. During treatment, we observed a progressive increase in haemoglobin (Hb) levels, with a statistically significant difference compared with baseline after 3 months of treatment (p=0.02). In parallel we registered the increase in RBC count, without the need to perform RBC transfusions after ANF starting. Overall disease activity significantly improved during the follow-up, with significant reduction of mean SLEDAI-2k values after 6 months of treatment (p=0.01).

CONCLUSION

In the present case-series study, we provide the first report about the benefit of ANF in the treatment of SLE-related AIHA, a rare but potentially severe manifestation associated with increased morbidity and mortality. In our cohort, ANF treatment was associated with a rapid and sustained increase in Hb levels, evident already at 1 month and progressively improving up to 6 months.