Long-Term Exposure of HIV Type 1-Infected Cell Cultures to Combinations of the Novel Quinoxaline GW420867X with Lamivudine, Abacavir, and a Variety of Nonnucleoside Reverse Transcriptase Inhibitors

2000 ◽  
Vol 16 (6) ◽  
pp. 517-528 ◽  
Author(s):  
Jan Balzarini ◽  
Erik De Clercq ◽  
An Carbonez ◽  
Vikki Burt ◽  
Jörg-Peter Kleim
1999 ◽  
Vol 43 (12) ◽  
pp. 2893-2897 ◽  
Author(s):  
Jeffrey W. Corbett ◽  
Soo S. Ko ◽  
James D. Rodgers ◽  
Susan Jeffrey ◽  
Lee T. Bacheler ◽  
...  

ABSTRACT A research program targeted toward the identification of expanded-spectrum nonnucleoside reverse transcriptase inhibitors which possess increased potency toward K103N-containing mutant human immunodeficiency virus (HIV) and which maintain pharmacokinetics consistent with once-a-day dosing has resulted in the identification of the 4-cyclopropylalkynyl-4-trifluoromethyl-3,4-dihydro-2(1H)quinazolinones DPC 961 and DPC 963 and the 4-cyclopropylalkenyl-4-trifluoromethyl-3,4-dihydro-2(1H)quinazolinones DPC 082 and DPC 083 for clinical development. DPC 961, DPC 963, DPC 082, and DPC 083 all exhibit low-nanomolar potency toward wild-type virus, K103N and L100I single-mutation variants, and many multiply amino acid-substituted HIV type 1 mutants. This high degree of potency is combined with a high degree of oral bioavailability, as demonstrated in rhesus monkeys and chimpanzees, and with plasma serum protein binding that can result in significant free levels of drug.


2003 ◽  
Vol 47 (9) ◽  
pp. 2951-2957 ◽  
Author(s):  
Miguel Stevens ◽  
Christophe Pannecouque ◽  
Erik De Clercq ◽  
Jan Balzarini

ABSTRACT A new class of pyridine oxide derivatives as inhibitors of human immunodeficiency virus type 1 (HIV-1) and/or HIV-2 replication in cell culture has been identified. The compounds, which specifically inhibit HIV-1, behave as typical nonnucleoside reverse transcriptase inhibitors (NNRTIs). The most active congener of this group, JPL-133 (UC-B3096), has a 50% effective concentration of 0.05 μg/ml for HIV-1(IIIB) with a selectivity index of approximately 760 in CEM cell cultures. However, the cytostatic activity of most pyridine oxide derivatives highly depended on the nature of the cell line. All compounds, including those pyridine oxide derivatives that inhibit both HIV-1 and HIV-2 replication, select for NNRTI-characteristic mutations in the HIV-1 reverse transcriptase of HIV-infected cell cultures (i.e., Lys103Asn, Val108Ile, Glu138Lys, Tyr181Cys and Tyr188His). These amino acid mutations emerged mostly through transition of guanine to adenine or adenine to guanine in the corresponding codons of the reverse transcriptase (RT) gene. The HIV-1-specific pyridine oxide derivatives lost their antiviral activity against HIV-1 strains containing these mutations in the RT. However, most compounds retained pronounced antiviral potency against virus strains that contained other NNRTI-characteristic RT mutations, such as Leu100Ile and Val179Asp. Furthermore, the complete lack of inhibitory activity of the pyridine oxide derivatives against recombinant HIV-2 RT and partial retention of anti-HIV-1 activity against HIV-1 strains that contain a variety of HIV-1-characteristic mutations suggest that the pyridine oxide derivatives must have a second target of antiviral action independent from HIV-1 RT.


2002 ◽  
Vol 46 (6) ◽  
pp. 1851-1856 ◽  
Author(s):  
Dimitrios Motakis ◽  
Michael A. Parniak

ABSTRACT It was previously found that certain nonnucleoside reverse transcriptase inhibitors (NNRTI) possess virucidal activity against human immunodeficiency virus type 1 (HIV-1), and it was suggested that the tight-binding mode of inhibition of reverse transcriptase might be important for this virucidal activity (Borkow et al., J. Virol. 71:3023-3030, 1997). To test this, we compared six different NNRTI, including three tight-binding NNRTI, namely UC781, efavirenz (EFV) (Sustiva), and 5-chloro-3-phenylsulfonylindole-2-carboxamide (CSIC), and three rapid-equilibrium NNRTI, delavirdine (DLV) (Rescriptor), nevirapine (NVP) (Viramune), and UC84, in a variety of virucidal tests. Incubation of isolated HIV-1 virions with UC781, EFV, or CSIC rapidly inactivated the virus, whereas DLV, NVP, and UC84 were ineffective in this respect. Exposure of H9+ cells chronically infected by HIV-1 to the tight-binding NNRTI abolished the infectivity of nascent virus subsequently produced by these cells following removal of extracellular drug, thereby preventing cell-to-cell virus transmission in the absence of exogenous drug. In contrast, cell-to-cell transmission of HIV was blocked by DLV, NVP, and UC84 only when the drug remained in the extracellular medium. Pretreatment of uninfected lymphocytoid cells with UC781, EFV, or CSIC, but not DLV, NVP, or UC84, protected these cells from subsequent HIV-1 infection in the absence of extracellular drug. The protective effect was dependent on both the dose of NNRTI and the viral load. The overall virucidal efficacy of the tight-binding NNRTI tested was CSIC > UC781 ≃ EFV. We conclude that the tight-binding mode of inhibition is an essential characteristic for virucidal NNRTI and that antiviral potency is an insufficient predictor for virucidal utility of NNRTI.


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