Long-term effects of the new direct antiviral agents (DAAs) therapy for HCV-related mixed cryoglobulinaemia without renal involvement: a multicentre open-label study.

Objectives: To investigate the long-term effects and safety of new direct anti-viral agents (DAAs) in patients with hepatitis C virus (HCV)-related mixed cryoglobulinaemia (MC) without renal involvement.

Methods: The study enrolled 22 consecutive patients, 19 received sofosbuvir-based regimen and three patients received other DAAs, individually tailored according to latest guidelines. As of December 2016, the median length of follow-up was 17 months (range 13-21).

Results: Extra-hepatic manifestations at enrollment were: purpura and arthralgia (12 cases), peripheral neuropathy (10 cases) and marginal zone B- lymphomas (2 cases). After a four-week DAA therapy, all patients became HCV- negative. Moreover, after 48 weeks since the beginning of DAA treatment, sustained regression of purpura and arthralgias was observed respectively in eight and in nine cases; peripheral neuropathy improved in seven cases, and cryocrit median values decreased from three (1-20) at baseline to two (1-12) after 48 weeks. Two cases with indolent marginal zone lymphomas did not show any haematological response: size and number of the involved nodes remained unchanged. In addition, the monoclonal B-cell population found in the peripheral blood in four cases did not disappear after recovery from HCV- RNA. Mild side effects occurred in nine patients, but six patients developed ribavirin-related anaemia requiring reduction of ribavirin dose.

Conclusions: DAA therapy is safe and effective to eradicate HCV in MC, but seems associated with satisfactory clinical response in mild or moderate cryoglobulinaemic vasculitis and no response in B-NHL.