Pharmacokinetics, Safety and Immunogenicity of RPH-104 at a New Dosage and Different Doses Via Single Subcutaneous and Intravenous Administration in Healthy Volunteers

This clinical study is a single-center, simple-blind, randomized, comparative phase I clinical study conducted in 3 parallel cohorts:

In cohort A, a simple blind design is proposed with a single intravenous administration of the study drug at 3 increasing doses (N = 30, 10 volunteers per dose group): 80 mg, 160 mg, 320 mg

In cohort B, a simple blind design is proposed with a single subcutaneous administration of the study drug (80 mg/mL; 320 mg) compared to placebo (N = 20, 10 volunteers per drug and placebo group)

In cohort C, a simple blind design is proposed with a single subcutaneous administration of the study drug in two dosages (40 mg/mL and 80 mg/mL) in one dose (80 mg) to confirm the equivalence of these dosages (N = 80, 40 volunteers in each group)

The study will include the following periods:

1. Screening period: days -6 to -1 (before randomization and inclusion in the study) 2. Randomization: day 0 3. Main study period:days 1 to 50 (± 1)

The main period includes a single hospitalization of volunteers for at least 24 hours, as well as 9 outpatient visits in cohort A and 14 outpatient visits in cohorts B and C. It includes procedures related to the administration of the study drug, monitoring the study participant, and taking blood samples to measure the concentration of goflikicept, as well as a safety and immunogenicity panel 4. Safety monitoring period: days 51 - 61 (± 3). On day 61, a phone call will be made to collect information about safety

In order to monitor safety during the main sudy period, the following procedures will be carried out:

* In Cohort A, vital signs vital signs will be measured before drug administration and 15 min, 1 h, 2 h, 4 h, 12 h and 24 h after drug administration on days 3-50; physical examination will be performed on days 2, 6, 16, 30, 40, 50; electrocardiography (ECG) on days 3, 23, 50 day; assessment of hypersensitivity reactions to the drug in 2 h, 12 h, 24 h after the start of drug administration and on day 3; clinical blood test, biochemical blood test on 3, 6, 16, 23, 50 day; coagulogram on 3, 16, 50 day; general urinalysis on 6, 16, 23, 50 day. * In Cohort B and C, vital signs vital signs will be measured before drug administration and in 2 h, 12 h and 24 h after drug administration on days 3-50; physical examination will be performed on days 2, 6, 16, 30, 40, 50; ECG on days 5, 23, 50 day; assessment of hypersensitivity reactions to the drug in 2 h, 12 h, 24 h after the start of drug administration and on day 3; clinical blood test, biochemical blood test on 5, 9, 16, 30, 50 day; coagulogram on 5, 16, 50 day; general urinalysis on 5, 16, 30, 50 day * Women with preserved reproductive potential will additionally undergo blood analysis for hCG during screening, followed by a urine pregnancy test the day before the administration of RPH-104 (Day 0) and on Day 50