Eligibility Criteria:
Inclusion Criteria:
1. Patient who fully completed per protocol a 24-week randomized withdrawal period (for the first 20 randomized patients), or the preparation therapy after the end of enrolment into the randomized withdrawal period in the main study CL04018068.
OR Patient who fully completed per protocol the study CL04018077 (after repeated screening).
2. Voluntarily signed and dated Patient Informed Consent Form for participation in this study.
3. The patient's ability and willingness, according to the investigator, to follow the schedule of visits, the study procedures and follow the protocol requirements, including the following:
* Come to the study site every 2 weeks for the study drug administration by qualified site staff; or
* Learn how to perform subcutaneous injections and do it on their own at home as per protocol of this study.
Exclusion Criteria:
1. Unwillingness or inability of the patient to perform the study procedures in accordance with the Protocol.
2. Any medically important event that was reported in a patient during his/her participation in the main study CL04018068, and, in the opinion of the Investigator, is a reason for not including this patient in this open-label study.
3. Pregnant and lactating women or women planning pregnancy during the study or within 2 months after the last dose of the study drug.
4. Women of childbearing potential who do NOT agree to use highly effective contraception methods throughout the study, starting from the moment of signing the informed consent form and for at least 8 weeks after the last dose of the study drug.
OR Men who are sexually active and do NOT agree to use highly effective contraception methods throughout the study, starting from the moment of signing the informed consent form and for at least 8 weeks after the last dose of the study drug.
Highly effective contraception methods include:
* sterilization in women: surgical bilateral removal of the ovaries (with or without removal of the uterus) or ligation of the fallopian tubes at least 6 weeks before the start of the study therapy. In the case of removal of only the ovaries, the reproductive status of a woman should be confirmed by a subsequent assessment of hormone level;
* sterilization in men, at least 6 months before the start of the study therapy with proper documentation of the absence of sperm in the ejaculate after vasectomy. For women participating in the study, a sexual partner after a vasectomy should be the only partner;
* using a combination of any two of the following methods (a+b or a+c or b+c):
1. oral, injectable or implanted hormonal contraceptives; in the case of the use of oral contraceptives, women should continuously use the same drug for at least 3 months before the start of the study therapy;
2. an intrauterine device or contraceptive system;
3. barrier methods of contraception: condom or occlusive cap (diaphragm or cervical cap/contraceptive vaginal ring) with spermicidal foam/gel/film/cream/vaginal suppository.
5. The need to use a live (attenuated) vaccine during the study or within 3 months after the last dose of the study drug. Live attenuated vaccines include vaccines against the following viruses: measles, rubella, mumps, chickenpox, rotavirus, flu (as a nasal spray), yellow fever, polio (oral polio vaccine); vaccines against tuberculosis (BCG), typhoid fever (oral typhoid vaccine) and typhus (typhus vaccine). Immunocompetent family members of the patient should not be vaccinated with the oral polio vaccine during the patient's participation in the study.
6. Other medical conditions or laboratory abnormalities, which may increase the potential risk associated with participation in the study and treatment with the study drug, or may affect the interpretation of the results of the study, and which, in the opinion of the Investigator lead to patient ineligibility for this study.
7. Parallel participation in other clinical trials (except for the main study CL04018068) at the time of screening or the use of any unapproved (investigational) drugs (except for RPH-104) less than 4 weeks or 5 half-lives (whichever is greater) before screening.
For patients undergoing repeated screening, the following criteria are additionally applicable:
8. Hypersensitivity to the test drug (RPH-104), and/or its components /excipients and/or drugs of the same chemical class.
9. Previous use of drugs:
* rilonacept - less than 6 weeks before the initial assessment (the day of the re-screening visit),
* kanakinumab - less than 12 weeks before the initial assessment (the day of the re-screening visit),
* anakinra - less than 5 days before the initial assessment (the day of the re-screening visit),
* drugs of the TNF inhibitor class, IL-6 inhibitors, janus kinase inhibitors - less than 12 weeks before the initial assessment (the day of the re-screening visit),- - immunosuppressants (azathioprine, cyclosoprine, mycophenolate, mofetil, tacrolimus, sirolimus, mercaptopurine) - less than 24 weeks before the initial assessment (the day of the re-screening visit),
* methotrexate - less than 2 weeks before the initial assessment (the day of the re-screening visit),
* any other biological drugs in less than 5 periods half-life before the start of therapy.
10. Any conditions or signs in the patient that, according to the investigator's judgement, indicate a disorder (suppression) of the patient's immune response and/or significantly increase the risk of immunomodulatory therapy, including, but not limited to, the following:
* active bacterial, fungal, viral or protozoal infection revealed at the beginning of the screening period;
* opportunistic infections and/or Kaposi's sarcoma at the beginning of the screening period;
* chronic bacterial, fungal or viral infection requiring systemic therapy at the beginning of the screening period;
* HIV-infection, hepatitis B or C (patients with treated hepatitis C and negative polymerase chain reaction (PCR) tests after 3 and 6 months are regarded as cured from hepatitis C and can be included in this study);
11. A history of active tuberculosis or the presence of risk factors or signs indicating the presence of active or latent infection caused by M. Tuberculosis, including but not limited to the following:
* living in specific conditions that increase the risk of contacts with tuberculosis-infected patients, such as prisons, gathering of homeless people etc. over the past year until the beginning of the main treatment period;
* occupational exposure at a medical institution in the settings of unprotected contact with patients with a high risk of tuberculosis or patients with tuberculosis during the last year before the start of the screening period;
* close contact, i.e. being in the same room (at home or in another confined environment) for an extended period of time (days or weeks rather than minutes or hours) with a person with active pulmonary tuberculosis within the past year prior to the beginning of the treatment period;
* test results indicating active tuberculosis or latent infection caused by M. Tuberculosis: positive result of QuantiFERON-TB/T-SPOT test.TB during the screening period; findings of chest X-ray exam in two views confirming pulmonary tuberculosis during the screening period.
12. History of alcohol abuse or psychoactive substances abuse as assessed by the Investigator.
13. Severe renal impairment: creatinine clearance by Cockcroft-Gault formula \<30 mL/min at the screening.
14. Presence of any of the following at the screening:
* absolute neutrophil count \<1.5 х 10\^9/L,
* white blood cells (WBC) count \<3.5 х 10\^9/L,
* platelet count \<100 х 10\^9/L,
* hemoglobin ≤ 80 g/L,
* glycated hemoglobin (HbA1c) ≥ 8% (to be evaluated only in patients with diabetes mellitus),
* alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) ≥ 3.0 х upper limit of normal (ULN),
* total bilirubin \>1.5 х ULN (except for cases of documented Gilbert's syndrome).