July 13, 2010

Antivirals Are Poorly Tolerated, Largely Ineffective Against HCV After Liver Transplantation

Authors and Disclosures

Journalist
Lara C. Pullen, PhD
President, Environmental Health Consulting, Oak Park, Illinois

July 13, 2010 (Hong Kong, China) — Results from a new study suggest that antiviral therapy should be used more judiciously in patients with hepatitis C virus (HCV) infection who have undergone liver transplantation.

Specifically, these patients should not be started on antiviral therapy in the first postoperative year unless there is clear evidence of histologic recurrence of HCV infection, investigator Michael Charlton, MD, from the Mayo Clinic College of Medicine in Rochester, Minnesota, told attendees here at the International Liver Transplantation Society 16th Annual International Congress.

The most common indication for liver transplantation in North America is HCV-related end-stage liver disease. Most of these transplant recipients go on to experience virological recurrence, which is a major cause of morbidity and mortality. Cirrhosis is diagnosed in 20% to 40% of patients in the 5 years after transplantation, Dr. Charlton noted during an interview with Medscape Medical News.

"I think the study highlights the difficulties we face in treating HCV infection in liver transplant recipients with our current tools — peginterferon and ribavirin. Most patients don't tolerate treatment and most of those who do tolerate treatment don't respond to it."

In the PHOENIX study, the Mayo Clinic team looked at the safety, tolerability, and safety of prophylactic peginterferon alfa-2a plus ribavirin therapy after liver transplantation in 115 patients randomized to treatment (55 patients) or observation (60 patients) 10 to 26 weeks after transplantation. The mean age in the prophylaxis group was 51.0 years (range, 35 to 68 years) and in the observation group was 53.5 years (range, 38 to 66 years). Patients in the prophylaxis group received peginterferon alfa-2a (135 µg/week for 4 weeks followed by 180 µg/week for 44 weeks) and ribavirin (initially dosed at 400 mg/day and escalated to 1200 mg/day).

Dr. Charlton reported sustained virologic response in 22% of the patients in the prophylaxis group and 21% of those in the observation group, who were treated if histologic recurrence was demonstrated.

When analyzed at 120 weeks on an intent-to-treat basis, the frequency of histologically confirmed HCV recurrence was similar in both groups (P = .725).

Prophylactic antiviral therapy had no effect on patient or graft survival. Antiviral therapy was poorly tolerated, and only 55.6% of the prophylaxis group and 28.6% of the observation group were able to tolerate more than 80% of the intended antiviral dosing.

Dr. Charlton added: "I hope the results will provoke new studies of strategies to improve the tolerability and efficacy of posttransplant antiviral therapy. The near-term advents of IL28b testing and the addition of protease inhibitors are eagerly awaited."

Brian B. Borg, MD, MHSc, from the Ochsner Multi-Organ Transplant Institute in New Orleans, Louisiana, added that after liver transplantation, "patients are on multiple immune suppressive regimens, especially in the early posttransplant period, and are prone to other comorbidities making them less optimal candidates for treatment. The treatment response is not as good as in pretransplant patients and adherence to current combination therapy is poor because of side effects and potential complications." Dr. Borg is not affiliated with the study, but spoke with Medscape Medical News about the implications of the research.

Other transplantation centers have found alternative strategies for dealing with this problem. Luca Cicalese, MD, from the Texas Transplant Center at the University of Texas Medical Branch in Galveston, told Medscape Medical News that "at the Texas Transplant Center, we start treatment for hepatitis C after liver transplant only when there is evidence of active infection. We are also using a particular immunosuppressive protocol (to reduce the risk of rejection) that is particularly designed to reduce the risk of recurrence of hepatitis C posttransplant in our patients, which has drastically reduced such occurrence." Dr. Cicalese was not involved with the study.

Dr. Charlton's study was funded entirely by Roche/Genentech, the makers of peginterferon alfa-2a and ribavirin.
Dr. Borg and Dr. Cicalese have disclosed no relevant financial relationships.

International Liver Transplantation Society (ILTS) 16th Annual International Congress: Abstract 0-162. Presented June 19, 2010.

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