Due to our increasing knowledge of mechanisms underlying pathogenic events in autoimmune rheumatic diseases, biologic agents have been further explored and tested in open and controlled clinical trials. Based on the results of placebo-controlled trials, monoclonal antibodies to CD4+ T cells have been found ineffective in treating rheumatoid arthritis. However, this type of monoclonal antibody might be useful for combination therapy with monoclonal antibody, against tumor necrosis factor-alpha. The most promising data have been collected from a placebo-controlled four-center study of monoclonal anti-tumor necrosis factor-alpha antibodies in rheumatoid arthritis patients. This type of treatment was demonstrated for the first time to effectively interfere with ongoing inflammatory processes. Undoubtedly, the progress in the development of biologic agents for the therapy of inflammatory rheumatic diseases is steadily improving. Thus, for the future, even better treatment principles for this group of diseases can be expected.