scholarly journals In Vitro Interactions between Apricitabine and Other Deoxycytidine Analogues

2007 ◽  
Vol 51 (8) ◽  
pp. 2948-2953 ◽  
Author(s):  
R. Bethell ◽  
J. De Muys ◽  
J. Lippens ◽  
A. Richard ◽  
B. Hamelin ◽  
...  

ABSTRACT Apricitabine is a novel deoxycytidine analogue reverse transcriptase inhibitor that is under development for the treatment of human immunodeficiency virus type 1 (HIV-1) infection. Apricitabine is phosphorylated to its active triphosphate by deoxycytidine kinase, which is also responsible for the intracellular phosphorylation of lamivudine (3TC) and emtricitabine (FTC); hence, in vitro studies were performed to investigate possible interactions between apricitabine and these agents. Human peripheral blood mononuclear cells (PBMC) were incubated for 24 h with various concentrations of 3H-labeled or unlabeled apricitabine, 3TC, or FTC. Intracellular concentrations of parent compounds and their phosphorylated derivatives were measured by high-performance liquid chromatography. In other experiments, viral reverse transcriptase activity was measured in PBMC infected with HIV-1 bearing M184V in the presence of various concentrations of apricitabine and 3TC. [3H]apricitabine and [3H]3TC were metabolized intracellularly to form mono-, di-, and triphosphates. 3TC and FTC (1 to 10 μM) produced concentration-dependent decreases in apricitabine phosphorylation; in contrast, apricitabine at concentrations of up to 30 μM had no effect on the phosphorylation of 3TC or FTC. The combination of apricitabine and 3TC reduced the antiviral activity of apricitabine against HIV-1: apricitabine concentrations producing 50% inhibition of viral reverse transcriptase were increased two- to fivefold in the presence of 3TC. These findings suggest that nucleoside reverse transcriptase inhibitors with similar modes of action may show biochemical interactions that affect their antiviral efficacy. It is therefore essential that potential interactions between combinations of new and existing agents be thoroughly investigated before such combinations are introduced into clinical practice.

2007 ◽  
Vol 51 (8) ◽  
pp. 2943-2947 ◽  
Author(s):  
T. Holdich ◽  
L. A. Shiveley ◽  
J. Sawyer

ABSTRACT Apricitabine is a novel deoxycytidine analog reverse transcriptase inhibitor. In vitro apricitabine competes with other deoxycytidine analogues for intracellular phosphorylation mediated by deoxycytidine kinase. The topic of this study, the effect of concomitant administration of apricitabine and lamivudine on the plasma and intracellular pharmacokinetics of the two compounds, was investigated in healthy volunteers. Participants (n = 21; age, 18 to 30 years) received apricitabine at 600 mg twice daily, lamivudine at 300 mg once daily, and the two treatments in combination for 4 days each in random order. Plasma, urine, and intracellular pharmacokinetics were assessed on day 4 of each treatment period. Apricitabine was rapidly absorbed after oral administration, with peak concentrations being attained after a mean of 1.76 h. Coadministration with lamivudine had no significant effect on the plasma and urine pharmacokinetics of apricitabine. However, the formation of apricitabine triphosphate in peripheral blood mononuclear cells was markedly reduced after the coadministration of apricitabine and lamivudine than after the administration of apricitabine alone: the area under the concentration-time curve from 0 to 12 h for apricitabine triphosphate during combination treatment was ca. 15% of that seen after the administration of apricitabine alone. In contrast, apricitabine had no effect on the plasma pharmacokinetics of lamivudine or on the formation of lamivudine triphosphate in peripheral blood mononuclear cells. These results are consistent with in vitro findings that lamivudine inhibits the intracellular phosphorylation of apricitabine. In conjunction with similar in vitro observations for emtricitabine and apricitabine, these results suggest that apricitabine should not be coadministered with other deoxycytidine analogues for the treatment of human immunodeficiency virus infection.


2000 ◽  
Vol 11 (2) ◽  
pp. 135-140 ◽  
Author(s):  
Fatih M Uckun ◽  
Chen Mao ◽  
Sharon Pendergrass ◽  
Danielle Maher ◽  
Dan Zhu ◽  
...  

The composite non-nucleoside reverse transcriptase inhibitor (NNRTI) binding pocket model was used to study a number of thiourea analogues with different substitutions at the 4-phenyl position including N-[2-(4-methylphenyl)ethyl]-N′-[2-(5-bromopyridyl)]-thiourea (compound HI-244), which inhibited recombinant RT better than trovirdine or compound HI-275 with an unsubstituted phenyl ring. HI-244 effectively inhibited the replication of HIV-1 strain HTLVIIIB in human peripheral blood mononuclear cells with an IC50 value of 0.007 μM, which is equal to the IC50 value of trovirdine. Notably, HI-244 was 20 times more effective than trovirdine against the multidrug-resistant HIV-1 strain RT-MDR with a V106A mutation (as well as additional mutations involving the RT residues 74 V, 41L and 215Y) and seven times more potent than trovirdine against the NNRTI- resistant HIV-1 strain A17 with a Y181C mutation.


2015 ◽  
Vol 60 (3) ◽  
pp. 1393-1400 ◽  
Author(s):  
Lara E. Pereira ◽  
Pedro M. M. Mesquita ◽  
Anthony Ham ◽  
Tyana Singletary ◽  
Frank Deyounks ◽  
...  

We evaluated thein vivopharmacokinetics and used a complementaryex vivococulture assay to determine the pharmacodynamics of IQB3002 gel containing 1% IQP-0528, a nonnucleoside reverse transcriptase inhibitor (NNRTI), in rhesus macaques (RM). The gel (1.5 ml) was applied vaginally to 6 simian-human immunodeficiency (SHIV)-positive female RM. Blood, vaginal fluids, and rectal fluids were collected at 0, 1, 2, and 4 h. RM were euthanized at 4 h, and vaginal, cervical, rectal, and regional lymph node tissues were harvested. Anti-human immunodeficiency virus (HIV) activity was evaluatedex vivoby coculturing fresh or frozen vaginal tissues with activated human peripheral blood mononuclear cells (PBMCs) and measuring the p24 levels for 10 days after an HIV-1Ba-Lchallenge. The median levels of IQP-0528, determined using liquid chromatography-tandem mass spectroscopy (LC-MS/MS) methods, were between 104and 105ng/g in vaginal and cervical tissue, between 103and 104ng/g in rectal tissues, and between 105and 107ng/ml in vaginal fluids over the 4-h period. The vaginal tissues protected the cocultured PBMCs from HIV-1 infectionex vivo, with a viral inhibition range of 81 to 100% in fresh and frozen tissues that were proximal, medial, and distal relative to the cervix. No viral inhibition was detected in untreated baseline tissues. Collectively, the median drug levels observed were 5 to 7 logs higher than thein vitro50% effective concentration (EC50) range (0.21 ng/ml to 1.29 ng/ml), suggesting that 1.5 ml of the gel delivers IQP-0528 throughout the RM vaginal compartment at levels that are highly inhibitory to HIV-1. Importantly, antiviral activity was observed in both fresh and frozen vaginal tissues, broadening the scope of theex vivococulture model for future NNRTI efficacy studies.


1994 ◽  
Vol 5 (4) ◽  
pp. 278-281
Author(s):  
H. Samanta ◽  
R. Rose ◽  
A. K. Patick ◽  
C. M. Bechtold ◽  
J. Trimble ◽  
...  

A virus strain resistant to R82150, a non-nucleoside reverse transcriptase (NNRT) inhibitor (tetrahydro-imidazo [4,5, 1- jk] [1,4] benzodiazepine-2(1 H)-thione), was isolated following serial passage of HIV-1 RF in CEM-SS cells. The virus is cross-resistant to another non-nucleoside reverse transcriptase inhibitor, TGG-II-23A [1,4-dimethyl-1-[5,5-dimethyl-2-oxazoionyl]-naphthalen-2-one), but remains susceptible to AZT, DDI, D4T and phosphonoformate (PFA). DNA sequencing of reverse transcriptase genes from resistant virus indicated that R82150 selects for amino acid alterations Y181C and V108I. In vitro mutagenized reverse transcriptase and recombinant HIV-1 (pNL4-3) carrying either of the mutations have been generated. Genotypic and phenotypic analyses identified V108I as an unreported R82150-associated mutation. Both reverse transcriptase and viral resistance assays indicated that the resistance conferred by the V108I mutation is 7-fold less than that conferred by Y181C.


2009 ◽  
Vol 53 (9) ◽  
pp. 3887-3893 ◽  
Author(s):  
Shinichiro Hattori ◽  
Kazuhiko Ide ◽  
Hirotomo Nakata ◽  
Hideki Harada ◽  
Shinya Suzu ◽  
...  

ABSTRACT 4′-Ethynyl-2-fluoro-2′-deoxyadenosine (EFdA), a recently discovered nucleoside reverse transcriptase inhibitor, exhibits activity against a wide spectrum of wild-type and multidrug-resistant clinical human immunodeficiency virus type 1 (HIV-1) isolates (50% effective concentration, 0.0001 to 0.001 μM). In the present study, we used human peripheral blood mononuclear cell-transplanted, HIV-1-infected NOD/SCID/Janus kinase 3 knockout mice for in vivo evaluation of the anti-HIV activity of EFdA. Administration of EFdA decreased the replication and cytopathic effects of HIV-1 without identifiable adverse effects. In phosphate-buffered saline (PBS)-treated mice, the CD4+/CD8+ cell ratio in the spleen was low (median, 0.04; range, 0.02 to 0.49), while that in mice receiving EFdA was increased (median, 0.65; range, 0.57 to 1.43). EFdA treatment significantly suppressed the amount of HIV-1 RNA (median of 9.0 × 102 copies/ml [range, 8.1 × 102 to 1.1 × 103 copies/ml] versus median of 9.9 × 104 copies/ml [range, 8.1 × 102 to 1.1 × 103 copies/ml]; P < 0.001), the p24 level in plasma (2.5 × 103 pg/ml [range, 8.2 × 102 to 5.6 × 103 pg/ml] versus 2.8 × 102 pg/ml [range, 8.2 × 101 to 6.3 × 102 pg/ml]; P < 0.001), and the percentage of p24-expressing cells in the spleen (median of 1.90% [range, 0.33% to 3.68%] versus median of 0.11% [range, 0.00% to 1.00%]; P = 0.003) in comparison with PBS-treated mice. These data suggest that EFdA is a promising candidate for a new age of HIV-1 chemotherapy and should be developed further as a potential therapy for individuals with multidrug-resistant HIV-1 variants.


2015 ◽  
Vol 59 (8) ◽  
pp. 4882-4888 ◽  
Author(s):  
Weisi Xu ◽  
Jianxiong Zhao ◽  
Jianping Sun ◽  
Qianqian Yin ◽  
Yan Wang ◽  
...  

ABSTRACTNonnucleoside reverse transcriptase inhibitors (NNRTIs) are important components of the highly active antiretroviral therapy (HAART) used to treat human immunodeficiency type 1 virus (HIV-1). However, because of the emergence of drug resistance and the adverse effects of current anti-HIV drugs, it is essential to develop novel NNRTIs with an excellent safety profile, improved activity against NNRTI-resistant viruses, and enhanced activity against clinical isolates of different subtypes. Here, we have identified 1-[(benzyloxy)methyl]-6-(3,5-dimethylbenzyl)-5-iodopyrimidine-2,4(1H,3H)-dione (WPR-6), a novel NNRTI with a 50% effective concentration (EC50) of 2 to 4 nM against laboratory-adapted HIV-1 strain SF33 and an EC50of 7 to 14 nM against nucleoside reverse transcriptase inhibitor-resistant HIV-1 strain 7391 with a therapeutic index of >1 × 104. A panel of five representative clinical virus isolates of different subtypes circulating predominantly in China was highly sensitive to WPR-6, with EC50s ranging from 1 to 6 nM. In addition, WPR-6 showed excellent antiviral potency against the most prevalent NNRTI-resistant viruses containing the K103N and Y181C mutations. To determine whether WPR-6 selects for novel resistant mutants,in vitroresistance selection was conducted with laboratory-adapted HIV-1 strain SF33 on MT-4 cells. The results demonstrated that V106I and Y188L were the two dominant NNRTI-associated resistance mutations detected in the breakthrough viruses. Taken together, thesein vitrodata indicate that WPR-6 has greater efficacy than the reference HEPT analogue TNK651 and the marketed drug nevirapine against HIV-1. However, to develop it as a new NNRTI, further improvement of its pharmacological properties is warranted.


1995 ◽  
Vol 6 (6) ◽  
pp. 365-370 ◽  
Author(s):  
S. T. Ingate ◽  
M.-J. Camarasa ◽  
E. De Clercq ◽  
J. Balzarini

The L-isomer of the potent HIV-1-RT inhibitor TSAO-T has been stereospecifically synthesized and tested for its ‘ in vitro’ antiretroviral activity against HIV-1. Unlike the D-isomer, the L-isomer did not show appreciable inhibition of HIV-1 replication. The cytotoxicity was comparable with the cytotoxicity of the D-enantiomer.


2011 ◽  
Vol 56 (1) ◽  
pp. 341-351 ◽  
Author(s):  
Xiaofan Lu ◽  
Li Liu ◽  
Xu Zhang ◽  
Terrence Chi Kong Lau ◽  
Stephen Kwok Wing Tsui ◽  
...  

ABSTRACTNonnucleoside reverse transcriptase inhibitors (NNRTIs) are one of the key components of antiretroviral therapy drug regimen against human immunodeficiency virus type 1 (HIV-1) replication. We previously described a newly synthesized small molecule, 10-chloromethyl-11-demethyl-12-oxo-calanolide A (F18), a (+)-calanolide A analog, as a novel anti-HIV-1 NNRTI (H. Xue et al., J. Med. Chem. 53:1397–1401, 2010). Here, we further investigated its antiviral range, drug resistance profile, and underlying mechanism of action. F18 consistently displayed potent activity against primary HIV-1 isolates, including various subtypes of group M, circulating recombinant form (CRF) 01_AE, and laboratory-adapted drug-resistant viruses. Moreover, F18 displayed distinct profiles against 17 NNRTI-resistant pseudoviruses, with an excellent potency especially against one of the most prevalent strains with the Y181C mutation (50% effective concentration, 1.0 nM), which was in stark contrast to the extensively used NNRTIs nevirapine and efavirenz. Moreover, we induced F18-resistant viruses byin vitroserial passages and found that the mutation L100I appeared to be the dominant contributor to F18 resistance, further suggesting a binding motif different from that of nevirapine and efavirenz. F18 was nonantagonistic when used in combination with other antiretrovirals against both wild-type and drug-resistant viruses in infected peripheral blood mononuclear cells. Interestingly, F18 displayed a highly synergistic antiviral effect with nevirapine against nevirapine-resistant virus (Y181C). Furthermore,in silicodocking analysis suggested that F18 may bind to the HIV-1 reverse transcriptase differently from other NNRTIs. This study presents F18 as a new potential drug for clinical use and also presents a new mechanism-based design for future NNRTI.


2005 ◽  
Vol 16 (5) ◽  
pp. 295-302 ◽  
Author(s):  
Richard C. Bethell ◽  
Yolanda S. Lie ◽  
Neil T. Parkin

SPD754 (also known as AVX-754) is a deoxycytidine analogue nucleoside reverse transcriptase inhibitor (NRTI) with antiretroviral activity against HIV-1 and HIV-2 in vitro and against recombinant viruses containing thymidine analogue mutations (TAMs). In order to better establish the activity of SPD754 against HIV-1 containing TAMs, twelve panels of up to twenty clinical isolates with defined TAM combinations were selected from the ViroLogic database. Phenotypic viral susceptibility to SPD754 and five other NRTIs was tested using the PhenoSense HIV assay and expressed as median fold-change compared with a reference strain. In total, 215 isolates were selected, representing four TAM patterns in both pathways by which TAMs accumulate clinically. The presence of five TAMs in the 41, 215 pathway, at codons 41, 67, 210, 215, and 219 of reverse transcriptase (RT), produced a median 1.8-fold reduction in SPD754 susceptibility, compared with fold reductions to zidovudine, lamivudine, abacavir, didanosine and tenofovir of 438, 4.8, 4.5, 1.4 and 3.6, respectively. Five TAMs in the 67, 70, 219 pathway (at codons 41, 67, 70, 215 and 219) reduced SPD754 susceptibility by a median 1.3-fold, compared with fold reductions for the aforementioned NRTIs of 108, 3.2, 3.0, 1.3 and 2.5, respectively. M184V addition reduced SPD754 susceptibility by 1.8-fold in the presence or absence of TAMs. SPD754 retains a substantial proportion of its antiviral activity against HIV-1 containing multiple TAMs, with or without the M184V mutation. These data suggest that SPD754 is a promising new NRTI for the treatment of NRTI-experienced HIV-infected patients.


2017 ◽  
Vol 61 (7) ◽  
Author(s):  
Nicholas S. Giacobbi ◽  
Nicolas Sluis-Cremer

ABSTRACT Rilpivirine (RPV), dapivirine (DPV), and MIV-150 are in development as microbicides. It is not known whether they will block infection of circulating nonnucleoside reverse transcriptase inhibitor (NNRTI)-resistant human immunodeficiency virus type 1 (HIV-1) variants. Here, we demonstrate that the activity of DPV and MIV-150 is compromised by many resistant viruses containing single or double substitutions. High DPV genital tract concentrations from DPV ring use may block replication of resistant viruses. However, MIV-150 genital tract concentrations may be insufficient to inhibit many resistant viruses, including those harboring K103N or Y181C.


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