A prospective cross-over study comparing the effect of mycophenolate versus azathioprine on allograft function and viral load in liver transplant recipients with recurrent chronic HCV infection.

It has been suggested that Mycophenolate Mofetil (MMF) may have an antiviral effect in patients with recurrent HCV infection post-liver transplantation. We conducted a prospective cross-over study in liver transplant recipients with recurrent chronic HCV infection to examine whether substitution of azathioprine (AZA) with MMF would reduce HCV load and improve allograft function. Thirteen long standing HCV liver transplant recipients receiving AZA were enrolled in a 9-month prospective cross-over study. In the initial 3 months lead-in period, baseline viral loads and biochemistry were recorded. Following this, MMF was substituted for AZA at a dose of 1 gm twice/day for a period of 3 months after which patients were switched back to AZA and observed for a further 3 months. Viral loads, biochemical allograft function, and adverse effects were closely monitored during the study period. Thirteen patients (12 males and 1 female) were enrolled. The mean age was 54 (+/-8) years and the mean time from transplantation was 68 (+/-35) months. Baseline mean viral load was 0.74 x 10(6)(+/-0.47 x 10(6)) messenger RNA (mRNA) copies/ml. By the end of the MMF treatment period, the mean viral load increased to a level of 1.64 x 10(6) (+/-1.3 x 10(6)) mRNA copies/ml (P = 0.026) compared to baseline. The increase in viral load however was not associated with an increase in ALT level. In a cohort of 13 HCV liver transplant recipients with recurrent chronic HCV infection, substitution of azathioprine with MMF did not lead to a decrease in viral load.