AIM: To characterize and evaluate the therapeuti efficacy of bioartificial liver (BAL) as compared to tha of continuous hemodiafiltration (CHDF) with plasma exchange (PE), which is the current standard therapy fo fulminant hepatic failure (FHF) in Japan. METHODS: Pigs with hepatic devascularization were divided into three groups: (1) a non-treatment group (NT; n = 4); (2) a BAL treatment group (BAL; n = 4) (3) a PE + CHDF treatment group using 1.5 L of norma porcine plasma with CHDF (PE + CHDF, n = 4). Our BA system consisted of a hollow fiber module with 0.2 μm pores and 1 x 1010 of microcarrier-attached hepatocyte inoculated into the extra-fiber space. Each treatment wa initiated 4 h after hepatic devascularization. RESULTS: The pigs in the BAL and the PE + CHD groups survived longer than those in the NT group. The elimination capacity of blood ammonia by both BAL and PE + CHDF was significantly higher than that in NT Aromatic amino acids (AAA) were selectively eliminated by BAL, whereas both AAA and branched chain amino acids, which are beneficial for life, were eliminated by PE + CHDF. Electrolytes maintenance and acid-base balance were better in the CPE + CHDF group than that in the BAL group. CONCLUSION: Our results suggest that PE + CHDF eliminate all factors regardless of benefits, wherea BAL selectively metabolizes toxic factors such as AAA However since PE + CHDF maintain electrolytes and acid-base balance, a combination therapy of BAL plu CPE + CHDF might be more effective for FHF. AIM: To characterize and evaluate therapeuti efficacy of bioartificial liver (BAL) as compared to tha of continuous hemodiafiltration (CHDF) with plasma exchange (PE), which is the current standard therapy ful fulant hepatic failure (FHF) in Japan. METHODS: Pigs with hepatic devascularization were divided into three groups: (1) a non-treatment group (NT; n = 4); (2) a BAL treatment group 1.5 L of norma porcine plasma with CHDF (PE + CHDF, n = 4). Our BA system consisted of a hollow fiber module with 0.2 μm pores and 1 × 1010 of microcarrier-attached hepatocytes inoculated into the extra-fiber space. Each treatment wa initiated 4 h after hepatic devascularization. RESULTS: The pigs in the BAL and the PE + CHD groups survived longer than those in the NT group. The elimination capacity of blood ammonia by both BAL and PE + CHDF was significantly higher than that in NT Aromatic amino acids (AAA) were selectively eliminated by BAL, wh Ereas both AAA and branched chain amino acids, which are beneficial for life, were eliminated by PE + CHDF. Electrolytes maintenance and acid-base balance were better in the CPE + CHDF group than that in the the BAL group. CONCLUSION: Our results suggest that PE + CHDF eliminate all factors regardless of benefits, wherea BAL coupled metabolizes toxic factors such as AAA However since PE + CHDF maintain electrolytes and acid-base balance, a combination therapy of BAL plu CPE + CHDF might be more effective for FHF.