Familial Mediterranean Fever (FMF) represents the most common form of monogenic autoinflammatory disease [
1]. It is characterized by recurrent, self-limited, inflammatory attacks, lasting 1–3 days. FMF results from gain of function mutations in the
MEFV gene located on chromosome 16 which encodes pyrin, a 781-amino acid long protein expressed primarily in cells of the innate immune system. There, it serves as a negative regulator of a cytosolic cellular multiprotein complex termed the inflammasome, which mediates the activation of various inflammatory pathways in response to deleterious cellular insults (e.g., infection) and drives the maturation of the IL-1b and IL-18. Accordingly, dysregulated inflammasome activity results in a pro-inflammatory state and has been linked to autoinflammatory diseases [
2]. In FMF, the added pyrin activity leads to an unrestricted inflammasome activation, thereby resulting in a hyperinflammatory state [
2,
3]. Among the different mutations described in
MEFV, the most common is M694V, which has been shown to present in 20–65% of patients. Importantly, M694V homozygotes suffer from a more severe form of the disease, including frequent episodes and the need for higher colchicine doses to prevent attacks, as compared to patients with other mutations [
4]. Approximately 10–20% of individuals who meet diagnostic criteria for FMF have no identified mutations in the
MEFV gene [
5]. Colchicine, which still represents the mainstay of FMF treatment, has been shown to prevent FMF attacks in 60–65% of patients and to result in a partial remission in an additional 30–35% of patients [
6]. Moreover, colchicine is capable of eliminating the long-term risk of secondary amyloidosis, which is the most significant complication in FMF. An additional complication of FMF in the pediatric population is the negative impact on linear growth [
7], similar to observations in other chronic diseases in children [
8,
9]. Indeed, it has been shown that successful treatment with colchicine has a positive effect on both height and weight parameters in children with FMF [
10‐
12]. These studies suggest that colchicine improves growth by suppressing disease activity and inflammation. Yet, up to 10% of FMF patients do not respond to colchicine treatment, even under maximal doses and full compliance [
13]. In recent years, a growing understanding of the molecular basis behind FMF has resulted in a new generation of drugs, directed against IL-1. These include anakinra, which is a recombinant form of the naturally occurring IL-1 receptor antagonist [
14], and canakinumab, a high affinity, fully human monoclonal anti-IL-1b antibody [
15]. Both drugs are currently prescribed to colchicine-resistant or -intolerant FMF patients, although colchicine is still used in these patients to prevent amyloidosis, as the two biological drugs have not been consistently shown to have this effect. Both anakinra and canakinumab have a relatively favorable safety profile, with the most common side effects being injection site reactions and infections (typically of the upper respiratory tract) [
16,
17]. Despite the growing use in anti-IL1 drugs in FMF among children, data is still lacking in regard to long-term follow up. In addition, the information regarding the impact of these novel drugs on linear growth in children with FMF is minimal [
18]. Herein, we carried out a single center retrospective cohort study involving 22 pediatric FMF patients treated with anti-IL1 agents to evaluate their long-term growth response to treatment in addition to assessment the overall efficacy and safety of these agents.