This long-term open-label study is an extension of the core double blind, randomized, placebo-controlled study, CL04018065. It is planned that this study will include no more than 60 patients who completed the core study, where they received blinded therapy.~This study will have the following periods:~Screening period - within one day, Day 0, which is also the day of Visit 11 of the main study. This period envisages unblinding of the treatment groups determined in the main study (for not-unblinded patients) and determination of the eligibility for this study. Patients who do not meet the inclusion/exclusion criteria will not receive treatment with the study drug, such patients should attend a safety follow-up visit 6 weeks after the screening period (i.e. 8 weeks after the last injection of the study drug or placebo during the core study) with all procedures performed in accordance with the last planned visit of the safety follow-up (Visit 17), after which their participation in the study will be considered completed.~Treatment period - all patients included in this period will receive open-label treatment with RPH-104 for 54 weeks. The possible drug dose will be:~80 mg once every 2 weeks subcutaneously;~160 mg once every 2 weeks subcutaneously.~An injection of the study drug to patients is performed by qualified medical personnel every 2 weeks when the patient visits the study site; it is also possible for the patients to self-administer the drug at home (for which patients will be appropriately trained and provided with the necessary quantity of the drug, materials for the injection (including special containers for their disposal) and proper drug transportation).~Safety and efficacy assessments are performed at Visit 1, Visit 2 (after 2 weeks) and then every 4 weeks according to the visits schedule. Safety and efficacy assessments are performed at Visit 1, Visit 2 (after 2 weeks) and then every 4 weeks according to the visits schedule.If FMF attack is confirmed in a patient, then patient's therapy can be adjusted based on the informed decision of an investigator:~for patients who receive RPH-104 at a dose of 80 mg q2w, a dose can be increased to 160 mg q2w;~for patients who already receive the maximum dose of RPH-104 that is 160 mg q2w, the dose will be not increased; these patients will be able to continue therapy with the study drug at a dose of 160 mg at the justified investigator's discretion.~Reduction of the study drug dose is not planned in this study.~Safety follow-up period - 8 weeks. After patients receive the last dose of the study drug at Week 54 of the study, the treatment period will be considered completed and an 8 weeks period of safety follow-up will start. During this period patients will have to visit the study site twice at Week 4 and Week 8 after the last dose of the study drug for safety assessments. Patients who have discontinued open-label therapy with the study drug early for any reason, should perform two safety follow-up visits at Week 4 and Week 8 after the last dose of the study drug.
The primary purpose of this study is to assess the safety of the long-term treatment with RPH-104 at doses 80 mg or 160 mg once every 2 weeks in a population of patients with colchicine resistant or colchicine intolerant familial Mediterranean fever (FMF) who completed the core study, during which they received at least one dose of RPH-104. Long-term efficacy of RPH-104, the immunogenicity of the RPH-104, the pharmacokinetics of the RPH-104 and quality of life change in the population of patients receiving long-term treatment with RPH-104 will be assessed as well.