Idiopathic recurrent pericarditis - a new orphan autoinflammatory disease? A retrospective analysis of cases of idiopathic recurrent pericarditis and a design of а double-blind, randomized, placebo-controlled study to evaluate the efficacy and safety of RPH-104 treatment in patients with idiopathic recurrent pericarditis.

Aim To analyze cases of idiopathic recurrent pericarditis (IRP) in the structure of pericardial diseases of various origins from patient visits to the Multidisciplinary Federal Center.Material and methods A retrospective analysis of case records was performed for patients admitted to the V.A. Almazov National Medical Research Center from January 1, 2015 through January 1, 2020 for pericardial effusion of different etiologies.Results For the study period, 4 981 new cases of pericardial damage of different etiologies were found. Among these cases, postpericardiotomy syndrome accounted for 4 360 cases and pericarditis for 621 cases. IRP was detected in 34 cases, which amounted to 5.4 %. Based on the study data, the estimated IRP prevalence in the Russian Federation can be 1.1 cases per 100 thousand population.Conclusion IRP should be regarded as a new autoinflammatory disease, the prevalence of which borders on that of adult Still disease and should be addressed within the concept of orphan diseases. Current knowledge of the pathogenesis and data from recent studies demonstrated a great importance of interleukin-1 blockade as a leading mechanism for achieving remission. This has justified conduction of a randomized clinical study at the Center.