ABSTRACT
Despite the progress of the past two decades, there is still considerable need for safe, efficacious drugs that target human immunodeficiency virus (HIV). This is particularly true for the growing number of patients infected with virus resistant to currently approved HIV drugs. Our high throughput screening effort identified a benzophenone template as a potential nonnucleoside reverse transcriptase inhibitor (NNRTI). This manuscript describes our extensive exploration of the benzophenone structure-activity relationships, which culminated in the identification of several compounds with very potent inhibition of both wild type and clinically relevant NNRTI-resistant mutant strains of HIV. These potent inhibitors include 70h (GW678248), which has in vitro antiviral assay IC(50) values of 0.5 nM against wild-type HIV, 1 nM against the K103N mutant associated with clinical resistance to efavirenz, and 0.7 nM against the Y181C mutant associated with clinical resistance to nevirapine. Compound 70h has also demonstrated relatively low clearance in intravenous pharmacokinetic studies in three species, and it is the active component of a drug candidate which has progressed to phase 2 clinical studies.
Subject(s)
Anti-HIV Agents/chemical synthesis , Benzophenones/chemical synthesis , HIV Reverse Transcriptase/metabolism , HIV-1/drug effects , Nitriles/chemical synthesis , Reverse Transcriptase Inhibitors/chemical synthesis , Sulfonamides/chemical synthesis , Alkynes , Animals , Anti-HIV Agents/pharmacokinetics , Anti-HIV Agents/pharmacology , Benzophenones/pharmacokinetics , Benzophenones/pharmacology , Benzoxazines , Cell Line , Cyclopropanes , Dogs , Drug Resistance, Viral , HIV-1/genetics , Humans , Macaca fascicularis , Male , Mutation , Nevirapine/pharmacology , Nitriles/pharmacokinetics , Nitriles/pharmacology , Oxazines/pharmacology , Reverse Transcriptase Inhibitors/pharmacokinetics , Reverse Transcriptase Inhibitors/pharmacology , Structure-Activity Relationship , Sulfonamides/pharmacokinetics , Sulfonamides/pharmacologyABSTRACT
GW678248, a novel nonnucleoside reverse transcriptase inhibitor, has been evaluated for anti-human immunodeficiency virus activity in a variety of in vitro assays against laboratory strains and clinical isolates. When GW678248 was tested in combination with approved drugs in the nucleoside and nucleotide reverse transcriptase inhibitor classes or the protease inhibitor class, the antiviral activities were either synergistic or additive. When GW678248 was tested in combination with approved drugs in the nonnucleoside reverse transcriptase inhibitor class, the antiviral activities were either additive or slightly antagonistic. Clinical isolates from antiretroviral drug-experienced patients were selected for evaluation of sensitivity to GW678248 in a recombinant virus assay. Efavirenz (EFV) and nevirapine (NVP) had > or = 10-fold increases in their 50% inhibitory concentrations (IC50s) for 85% and 98% of the 55 selected isolates, respectively, whereas GW678248 had a > or = 10-fold increase in the IC50 for only 17% of these isolates. Thus, 81 to 83% of the EFV- and/or NVP-resistant viruses from this data set were susceptible to GW678248. Virus populations resistant to GW678248 were selected by in vitro dose-escalating serial passage. Resistant progeny viruses recovered after eight passages had amino acid substitutions V106I, E138K, and P236L in the reverse transcriptase-coding region in one passage series and amino acid substitutions K102E, V106A, and P236L in a second passage series.
Subject(s)
Anti-HIV Agents/pharmacology , HIV Reverse Transcriptase/antagonists & inhibitors , HIV-1/drug effects , Nitriles/pharmacology , Reverse Transcriptase Inhibitors/pharmacology , Sulfonamides/pharmacology , Acquired Immunodeficiency Syndrome/drug therapy , Antiretroviral Therapy, Highly Active , Cell Line , Dose-Response Relationship, Drug , Drug Resistance, Viral , Drug Therapy, Combination , HIV Reverse Transcriptase/genetics , HIV-1/genetics , Humans , PhenotypeABSTRACT
The compound GW678248 is a novel benzophenone nonnucleoside reverse transcriptase inhibitor (NNRTI). Preclinical assessment of GW678248 indicates that this compound potently inhibits wild-type (WT) and mutant human immunodeficiency virus type 1 (HIV-1) reverse transcriptase in biochemical assays, with 50% inhibitory concentrations (IC(50)s) between 0.8 and 6.8 nM. In HeLa CD4 MAGI cell culture virus replication assays, GW678248 has an IC(50) of < or =21 nM against HIV-1 isogenic strains with single or double mutations known to be associated with NNRTI resistance, including L100I, K101E, K103N, V106A/I/M, V108I, E138K, Y181C, Y188C, Y188L, G190A/E, P225H, and P236L and various combinations. An IC(50) of 86 nM was obtained with a mutant virus having V106I, E138K, and P236L mutations that resulted from serial passage of WT virus in the presence of GW678248. The presence of 45 mg/ml human serum albumin plus 1 mg/ml alpha-1 acid glycoprotein increased the IC(50) approximately sevenfold. Cytotoxicity studies with GW678248 indicate that the 50% cytotoxicity concentration is greater than the level of compound solubility and provides a selectivity index of >2,500-fold for WT, Y181C, or K103N HIV-1. This compound exhibits excellent preclinical antiviral properties and, as a prodrug designated GW695634, is being developed as a new generation of NNRTI for the treatment of HIV-1 in combination with other antiretroviral agents.
Subject(s)
Anti-HIV Agents/pharmacology , Antiviral Agents/pharmacology , Benzophenones/chemistry , HIV-1/drug effects , Reverse Transcriptase Inhibitors/pharmacology , Anti-HIV Agents/therapeutic use , Antiviral Agents/therapeutic use , Cell Culture Techniques , Cell Line, Tumor , Cells, Cultured , Cytotoxicity Tests, Immunologic , Drug Evaluation, Preclinical , Drug Resistance, Viral , HIV-1/genetics , HeLa Cells , Humans , Inhibitory Concentration 50 , Jurkat Cells , Leukocytes, Mononuclear/cytology , Leukocytes, Mononuclear/virology , Molecular Structure , Mutation , Orosomucoid/metabolism , Reverse Transcriptase Inhibitors/chemistry , Reverse Transcriptase Inhibitors/therapeutic use , Serum Albumin/metabolism , U937 Cells , Virus Replication/drug effectsABSTRACT
HIV-1 nonnucleoside reverse transcriptase inhibitors (NNRTIs) are part of the combination therapy currently used to treat HIV infection. The features of a new NNRTI drug for HIV treatment must include selective potent activity against both wild-type virus as well as against mutant virus that have been selected by use of current antiretroviral treatment regimens. Based on analogy with known HIV-1 NNRTI inhibitors and modeling studies utilizing the X-ray crystal structure of inhibitors bound in the HIV-1 RT, a series of substituted 2-quinolones was synthesized and evaluated as HIV-1 inhibitors.
Subject(s)
Anti-HIV Agents/chemical synthesis , Drug Resistance, Viral , HIV Reverse Transcriptase/chemistry , Quinolones/chemical synthesis , Reverse Transcriptase Inhibitors/chemical synthesis , Alkynes , Anti-HIV Agents/chemistry , Anti-HIV Agents/pharmacology , Benzoxazines , Binding Sites , Cell Line , Crystallography, X-Ray , Cyclopropanes , Drug Design , HIV Reverse Transcriptase/genetics , HIV Reverse Transcriptase/metabolism , HIV-1/drug effects , HIV-1/enzymology , Humans , Models, Molecular , Molecular Structure , Mutation , Oxazines/chemistry , Quinolones/chemistry , Quinolones/pharmacology , Reverse Transcriptase Inhibitors/chemistry , Reverse Transcriptase Inhibitors/pharmacology , Structure-Activity RelationshipABSTRACT
GW4511, GW4751, and GW3011 showed IC50 values < or =2 nM against wild type HIV-1 and <10 nM against 16 mutants. They were particularly potent against NNRTI-resistant viruses containing Y181C-, K103N-, and K103N-based double mutations, which account for a significant proportion of the clinical failure of the three currently marketed NNRTIs. The antiviral data together with the favorable pharmacokinetic data of GW4511 suggested that these benzophenones possess attributes of a new NNRTI drug candidate.
Subject(s)
Anti-HIV Agents/chemical synthesis , Benzophenones/chemical synthesis , HIV Reverse Transcriptase/antagonists & inhibitors , Reverse Transcriptase Inhibitors/chemical synthesis , Anti-HIV Agents/chemistry , Anti-HIV Agents/pharmacology , Benzophenones/chemistry , Benzophenones/pharmacology , Cell Line , Crystallography, X-Ray , Drug Resistance, Viral , HIV Reverse Transcriptase/chemistry , HIV Reverse Transcriptase/metabolism , HIV-1/drug effects , HIV-1/enzymology , HIV-1/genetics , Humans , Inhibitory Concentration 50 , Mutation , Protein Binding , Reverse Transcriptase Inhibitors/chemistry , Reverse Transcriptase Inhibitors/pharmacology , Structure-Activity RelationshipABSTRACT
The synthesis and evaluation of novel ultrashort-acting benzodiazepine (USA BZD) agonists is described. A BZD scaffold was modified by incorporation of amino acids and derivatives. The propionate side chain of glutamic acid tethers an enzymatically labile functionality where the metabolite carboxylic acid displays markedly reduced BZD receptor affinity. The USA BZDs were characterized by full agonism profiles. Copyright2000 Elsevier Science Ltd.
Subject(s)
Benzodiazepines/chemical synthesis , Benzodiazepines/pharmacology , GABA-A Receptor Agonists , Animals , Benzodiazepines/pharmacokinetics , Chromatography, High Pressure Liquid , Humans , Postural Balance/drug effects , Rats , Receptors, GABA-A/metabolism , Structure-Activity RelationshipABSTRACT
The ultrashort-acting benzodiazepine (USA BZD) agonists reported previously have been structurally modified to improve aqueous solubility. Lactam-to-amidine modifications, replacement of the C5-haloaryl ring, and annulation of heterocycles are presented. These analogues retain BZD receptor potency and full agonism profiles.
