Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease of unknown cause, which primary affects joints, but can also affect other organic systems. The main feature of RA is a persistent symmetric synovitis that affects distal joints of extremities. Standard treatment include variety of drugs – analgesics, NSARs, glucocorticoids (GC) and DMARDs. By definition of HALMED, biological drugs are drugs which active substance is made or produce by biological source – human, animal or microbiologic. In Republic of Croatia, approved and the most commonly used biologic and targeted synthetic DMARDs are TNF-α inhibitors, IL-6 inhibitors, inhibitors of lymphocytes type B and JAK inhibitors. The aim of this study was to determine how many patients treated with biological drugs survived 12 months on a therapy with first biologic drugs, and what was the outcome of a disease. Other aims were to evaluate the frequency and reasons of discontinuation of a therapy, frequency of side effects and comparison of two groups of drugs (TNF-α inhibitors and other ihibitors). This study included 49 patients with RA with an average age of 49,63 (± 12,12),and average duration of illness before treatment with biologic drugs 11.31 ± 6.55 years. In the analyzed group, 34 (69,39%) of patients started biologic treatment with TNF-α inhibitors, whereas 15 (30,61%) of patients started their treatment using some other biological drugs (IL-6 inhibitors, inhibitors of lymphocytes type B and JAK inhibitors). The course of therapy on the first biologic drug was monitored for a period of 12 months. Results showed that 39 (79,59%) of patients survived 12 months being treated with biologic drug. From the survivors, following EULAR guidelines, remission is established in 20 (51,28%) of patients, whereas 6(15,38%) of patients showed low activity of a disease. The most common reason of discontinuation of treatment was primary inefficient of a drug (70%). The percentage of side effects was 28,57%. Comparing two groups of drugs, group of other inhibitors (non TNF-α inhibitors) showed higher percentage of patients who survived 12 months on a therapy (86,67% vs 76,47%). Results also showed greater alteration of disease activity in patients using non TNF-α inhibitors (ΔDAS28 3,65 vs 2,95)