Randomized Controlled Trial in Patients on Long-term Colchicine With Colchicine-resistant Familial Mediterranean Fever (FMF) to Evaluate the Efficacy of On-demand Anakinra Treatment for Painful Attacks in Patients Who Refuse Continuous Daily Therapy

KIN-ATTACK-FMF will be the first randomized prospective study comparing the efficacy of on-demand anakinra versus standard of care treatment in patients with colchicine resistant symptoms of FMF who refuse continuous daily therapy.

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease (100,000 people worldwide and 7500 in France). It causes monthly recurrent febrile abdominal pain with a biological inflammatory syndrome.

To prevent FMF attacks and development of inflammatory amyloidosis (IA) daily oral colchicine is the first line recommended treatment. 10 to 15% of patients are resistant to colchicine: persistence of 1attack/month over a period of 3 months (in spite of taking the maximum tolerated dose of colchicine daily). Subcutaneous anti-interleukin 1 biotherapies were recently allowed in France combined to daily oral colchicine for colchicine resistant FMF: anakinra (short-acting anti-IL1 drug, daily) or canakinumab (long acting monoclonal anti IL1 antibody, every 2 months). These treatments cost respectively 30 and 12,000 euros/injection.

If abdominal attacks are controlled by colchicine, patients still suffer from lower limb pains, particularly erysipelas like erythema and exertional myalgias, which are very disabling and require use of analgesics or anti-inflammatory. However, in the referral center, 20% of colchicine resistant FMF patients don't receive chronic anti IL1 treatment, despite an indication. Main reasons are: 1-they do not want to inject themselves every day (for anakinra); 2-women of childbearing age are afraid about the impact of biotherapies on their fetus; 3-some do not want to ask for 100% coverage because of the biotherapy cost; 4- the authorization for anti IL1 in FMF is very recent and they want more certainty about its effectiveness.

The hypothesis of the study is that on-demand use of Anakinra from onset of attack until 24 hours of remission (during 7 days maximum) associated with chronic daily colchicine as background treatment in case of attack could stop it, thus reducing its length and pain compared to standard of care treatment which includes only classical antalgics with colchicine in patients refusing chronic daily anti IL1 treatment.

In the experimental arm, patients receive on demand anakinra treatment (100 mg/d from the prodromal phase of the attack until 24 hours of remission (during 7 days maximum) associated with daily colchicine. In the control arm, patients receive analgesics associated with daily colchicine.

50 participants should be included in the study during a period of 24 months with a 6 months participation period (treatment + follow up)

It's a Multicenter national study including 11 centers.

• Cumulative days of FMF attack treatment from randomization to 6 months [Срок оценки: At Months 0 (baseline), Month 1, Month 3 and Month 6]
• AIDAI (Auto-inflammatory Diseases activity index) score [Срок оценки: At Months 0 (baseline), Month 1, Month 3 and Month 6]
• Number of painful days and severity of FMF attacks occurring between randomization and M6 [Срок оценки: At Months 0 (baseline), Month 1, Month 3 and Month 6]
• Quality of life score measured by EuroQOL questionnaire (EQ-5D5L) [Срок оценки: At Months 0 (baseline), Month 1, Month 3 and Month 6]
• Number of local cutaneous reactions at 6 months (erythema and oedema involving the injection sites) in the anakinra arm [Срок оценки: At Months 0 (baseline), Month 1, Month 3 and Month 6]
• Proportion of Adverse events [Срок оценки: At Months 0 (baseline), Month 1, Month 3 and Month 6]