Objective: To retrospectively assess and analyze the clinical efficacy and safety of off-label interleukin-1 (IL-1) blockade with anakinra during pregnancy of patients with familial Mediterranean fever (FMF).

Methods: Retrospective analysis of clinical and laboratory parameters making use of an electronic database system. Detailed descriptions of the genotype and phenotype of FMF are given and the course of the pregnancy and fetal development are reported.

Results: The data of three patients and a total of four pregnancies under treatedment with anakinra were analyzed. All patients were of Mediterranean origin, fulfilled the Tel Hashomer criteria for diagnosis of FMF and had a confirmed mutation in the MEFV gene. In all patients, treatment with anakinra was initiated due to an insufficient treatment response to colchicine. Anakinra led to a rapid response in all patients. In three pregnancies anakinra treatment was continued during the whole pregnancy, while in one pregnancy anakinra was started in the second trimester because of uncontrolled FMF activity. Fetal development was normal in all pregnancies. In two patients the fetuses were carried to term, while in one patient a primary cesarean section was carried out in week 33 because of an increased risk for complications. All children showed an unremarkable early childhood development without any signs of an existing disease.

Conclusion: The data of our retrospective analysis suggest that IL-1-blockade by anakinra is an effective and safe treatment in pregnant women suffering from FMF, which can reliably prevent disease flares. In the four pregnancies presented the use of anakinra did not result in impaired fetal and (early) childhood development.