Finally, other enzymes in the liver easily dislodged the phosphate group from
the nucleotide analogue, rendering the compound ineffective.
Results from three Phase III clinical trials (ION - 1, ION - 2 and ION - 3) evaluating the investigational once - daily fixed - dose combination of
the nucleotide analogue polymerase inhibitor sofosbuvir (SOF) 400 mg and the NS5A inhibitor ledipasvir (LDV) 90 mg, with and without ribavirin (RBV), for the treatment of genotype 1 chronic hepatitis C virus (HCV) infection have been presented at the International Liver CongressTM 2014.
A company called Pharmasset had been looking at a group of drugs known as
nucleotide analogues, which met some of these criteria, since the mid-2000s.
Because
the nucleotide analogues were water - soluble, they could not traverse the fatty lining of the intestine (fats and water do not mix) to reach the bloodstream and then the liver.