ABSTRACT
ABT-072 is a non-nucleoside HCV NS5B polymerase inhibitor that was discovered as part of a program to identify new direct-acting antivirals (DAAs) for the treatment of HCV infection. This compound was identified during a medicinal chemistry effort to improve on an original lead, inhibitor 1, which we described in a previous publication. Replacement of the amide linkage in 1 with a trans-olefin resulted in improved compound permeability and solubility and provided much better pharmacokinetic properties in preclinical species. Replacement of the dihydrouracil in 1 with an N-linked uracil provided better potency in the genotype 1 replicon assay. Results from phase 1 clinical studies supported once-daily oral dosing with ABT-072 in HCV infected patients. A phase 2 clinical study that combined ABT-072 with the HCV protease inhibitor ABT-450 provided a sustained virologic response at 24 weeks after dosing (SVR24) in 10 of 11 patients who received treatment.
Subject(s)
Cytosine/analogs & derivatives , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Hepacivirus/enzymology , Stilbenes/chemistry , Sulfonamides/chemical synthesis , Sulfonamides/pharmacology , Viral Nonstructural Proteins/antagonists & inhibitors , Administration, Oral , Biological Availability , Chemistry Techniques, Synthetic , Cytosine/chemical synthesis , Cytosine/chemistry , Cytosine/pharmacokinetics , Cytosine/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacokinetics , Humans , Permeability , Stereoisomerism , Sulfonamides/chemistry , Sulfonamides/pharmacokinetics , Tissue Distribution , Viral Nonstructural Proteins/chemistryABSTRACT
We describe here N-phenylpyrrolidine-based inhibitors of HCV NS5A with excellent potency, metabolic stability, and pharmacokinetics. Compounds with 2S,5S stereochemistry at the pyrrolidine ring provided improved genotype 1 (GT1) potency compared to the 2R,5R analogues. Furthermore, the attachment of substituents at the 4-position of the central N-phenyl group resulted in compounds with improved potency. Substitution with tert-butyl, as in compound 38 (ABT-267), provided compounds with low-picomolar EC50 values and superior pharmacokinetics. It was discovered that compound 38 was a pan-genotypic HCV inhibitor, with an EC50 range of 1.7-19.3 pM against GT1a, -1b, -2a, -2b, -3a, -4a, and -5a and 366 pM against GT6a. Compound 38 decreased HCV RNA up to 3.10 log10 IU/mL during 3-day monotherapy in treatment-naive HCV GT1-infected subjects and is currently in phase 3 clinical trials in combination with an NS3 protease inhibitor with ritonavir (r) (ABT-450/r) and an NS5B non-nucleoside polymerase inhibitor (ABT-333), with and without ribavirin.
Subject(s)
Anilides/pharmacology , Antiviral Agents/pharmacology , Carbamates/pharmacology , Genotype , Hepacivirus/drug effects , Sulfonamides/pharmacology , Uracil/analogs & derivatives , Viral Nonstructural Proteins/antagonists & inhibitors , 2-Naphthylamine , Anilides/chemistry , Anilides/pharmacokinetics , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacokinetics , Biological Availability , Carbamates/chemistry , Carbamates/pharmacokinetics , Cell Line , Drug Discovery , Hepacivirus/enzymology , Humans , Proline , Rats , Sulfonamides/chemistry , Sulfonamides/pharmacokinetics , Uracil/chemistry , Uracil/pharmacokinetics , Uracil/pharmacology , ValineABSTRACT
The synthesis and structure-activity relationships of a novel aryl uracil series which contains a fused 5,6-bicyclic ring unit for HCV NS5B inhibition is described. Several analogs display replicon cell culture potencies in the low nanomolar range along with excellent rat pharmacokinetic values.
Subject(s)
Bridged Bicyclo Compounds/chemistry , Bridged Bicyclo Compounds/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Uracil/antagonists & inhibitors , Viral Nonstructural Proteins/antagonists & inhibitors , Animals , Bridged Bicyclo Compounds/chemical synthesis , Bridged Bicyclo Compounds/pharmacokinetics , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacokinetics , Hepacivirus/enzymology , RNA-Dependent RNA Polymerase/antagonists & inhibitors , RNA-Dependent RNA Polymerase/metabolism , Rats , Structure-Activity Relationship , Uracil/pharmacology , Viral Nonstructural Proteins/metabolismABSTRACT
The synthesis of several pyrido[2,3-d]pyrimidine and pyrimido[4,5-d]pyrimidine analogs is described with one such analog possessing subnanomolar potency in both genotype 1a and 1b cell culture HCV replicon assays.