Abstract: Small inhibitory RNA (siRNA) molecules, which e.g. are purified and/or isolated, as an active in a medicament, which siRNA molecules are inhibitory RNA molecules that through RNA interference (RNAi) reduce or prevent expression of the p53 upregulated modulator of apoptosis (PUMA). The siRNA molecules can be administered as a medicament to a patient suffering from an impaired liver function or from liver damage for the treatment of a functionally impaired liver, for delaying a deterioration of liver function and/or for prevention of liver failure, especially in patients who suffer from a critical impairment of damage to the liver, e.g. for delaying the complete failure of liver function.