Direct-acting antiviral agents for HCV-associated cryoglobulinemic vasculitis. Does viral eradication always lead to the achievement of complete clinical and immunological responses?

Direct-acting antiviral agents (DAAs) are highly effective in treating HCV-associated cryoglobulinemic vasculitis (HCV-CV), achieving a sustained virological response (SVR) in 95—100% of patients. However, some patients still show immunological markers and sporadic vasculitis symptoms post-eradication. Objective. To evaluate clinical and immunological responses in patients with HCV-CV compared to patients with «asymptomatic» HCV-associated cryoglobulinemia (HCV-CG) after a course of DAA therapy during prolonged observation. Material and Methods. The study included 45 patients: 23 with HCV-CV and 22 with HCV-CG, who underwent antiviral therapy with DAAs. Clinical-immunological and virological data were assessed before treatment, at 12 and 48 weeks after treatment. Results. An SVR was achieved in 100% of patients after the DAA course. In patients with HCV-CV, an immunological response was observed in 56.5% by week 12 (SVR12) and 73.9% by week 48 (SVR48). Six patients (26.1%) did not achieve an immunological response by SVR48. The frequency of complete and partial clinical response by SVR12 among these patients was 65.2%, and by SVR48 — 78.3%. In 5 patients (21.7%) manifestations of HCV-CV persisted and/or relapsed. In patients with HCV-CG, the rate of complete and partial immunological response after DAA therapy was 77.3% at SVR12 and 86.3% at SVR48. Three patients showed no response, characterized by trace-level cryoglobulinemia. Conclusion. Most HCV-CV patients reach remission with DAA treatment. However, 20% of patients continue to exhibit/recurrent CV manifestations after treatment. Based on these observations, patients with HCV-CV, especially those with severe initial skin and kidney involvement, require long-term monitoring after achieving SVR.