Eighteen patients with fulminant hepatic failure due to various medical causes were listed for emergency liver transplantation and treated with extracorporeal albumin dialysis sessions using the molecular adsorbent recirculating system (MARS) at our center over a 74-month period. Due to improvement of liver function, transplantation could be avoided in 9 patients (50%, 95% confidence interval 29% to 71%) who fully recovered afterwards. This improvement rate was higher than the rate of improvement in the French cohort of fulminant hepatic failure patients with similar etiologies (19.3%, 95% confidence interval 14.9% to 24.6%, P = 0.002). In our 18 patients, there were no statistically significant differences in any baseline characteristics or in the time with liver failure meeting transplant criteria between the patients who improved while waiting and those who did not. However, the patients who improved received a greater number of sessions and a longer total duration of MARS therapy (all P < 0.001). In the whole study population, a MARS therapy duration > or =15 h was significantly associated with improvement of liver function without transplantation (adjusted adds ratio [OR] 65.76, 2.48-1743.11, P = 0.01). Tolerance of therapy was acceptable. These results suggest that MARS therapy could contribute to native liver recovery and is safe in patients on the waiting list for fulminant hepatic failure. A minimum duration of therapy (> or =15 h) could be necessary to expect significant liver function improvement.