Rituximab Helpful Against HCV Cryoglobulinemic Vasculitis

By David Douglas

NEW YORK (Reuters Health) Jan 13 - Research funded by the National Institutes of Health shows that rituximab is an effective treatment for refractory mixed cryoglobulinemic vasculitis in patients with hepatitis C.

"Unlike conventional forms of immunosuppressive therapy often used to treat this disease, rituximab was well tolerated and did not worsen the underlying viral hepatitis," said lead investigator Dr. Michael C. Sneller in email to Reuters Health.

Mixed cryoglobulinemic vasculitis is a relatively uncommon complication of hepatitis C virus (HCV) infection, as Dr. Sneller and his colleagues noted online December 6th in Arthritis & Rheumatism.
It's characterized by clonal expansion of B cells that produce IgM rheumatoid factor. The major manifestations are cutaneous vasculitis, arthralgia/arthritis, peripheral neuropathy, and membranoproliferative glomerulonephritis.

Pegylated interferon alpha and ribavirin can result in sustained remission, according to the researchers, but more than 50% of patients with HCV genotype 1, the most common in Europe and the Americas, do not respond.

Rituximab, however, can potentially deplete the expanded population of B cells - although there's been some concerns that it may increase HCV replication.
In an open label study, Dr. Sneller - based at the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland - and colleagues randomly assigned 24 patients to four weekly infusions of rituximab, or to continue with best available therapy. Everyone in the trial had either failed attempts to control the lymphoproliferative disease with interferon alpha and ribavirin, or they were intolerant of those drugs.

Patients in the rituximab group could continue on their immunosuppressive medications, but they could not increase the dose or receive new immunosuppressants or plasma exchange.
In the control group, patients were maintained on their current regimen and were allowed to increase or initiate new immunosuppressive treatments as needed.
At six months, 10 of the 12 rituximab patients (83.3%) were in remission, compared to only one control subject (8%).

Of the two rituximab patients not in remission at that point, one had to withdraw after two infusions because of febrile reactions. The other was in remission at four months but subsequently relapsed.
There were no adverse effects in terms of viremia or transaminase levels.

The researchers conclude that rituximab can induce sustained remissions, and "was well tolerated and did not appear to increase HCV replication or worsen the underlying hepatitis."
Dr. Sneller added in his email: "Rituximab may be a safer, more effective alternative to standard immunosuppressive therapy for patients with HCV-associated cryoglobulinemic vasculitis in whom antiviral therapy was not effective."

SOURCE: http://bit.ly/zeAest
Arthritis Rheum 2012.