SEARCH · PubMed Health

Results for “Reverse Transcriptase Inhibitors”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

PubMed2002

Discovery of second generation quinazolinone non-nucleoside reverse transcriptase inhibitors of HIV-1.

An intensive research effort to identify potent, viable drugs for the management of acquired immunodeficiency syndrome (AIDS) resulted in the development of SUSTIVA (efavirenz), the first non-nucleoside reverse transcriptase inhibitor (NNRTI) approved by the FDA as a preferred first-line therapy. The search for NNRTIs that possess a broader activity spectrum against mutant viral forms of human immunodeficiency syndrome type-I reverse transcriptase culminated in the discovery that trifluoromethyl-containing quinazolin-2(1H)-ones possess potent activity as non-nucleoside reverse transcriptase inhibitors (NNRTIs). This chapter reviews the discovery and structure activity relationships that resulted in the identification and subsequent preclinical and clinical development of four quinazolinone NNRTIs at the DuPont Pharmaceuticals Company.

Anti-HIV Agents↗

PubMed2005

Novel 8-substituted dipyridodiazepinone inhibitors with a broad-spectrum of activity against HIV-1 strains resistant to non-nucleoside reverse transcriptase inhibitors.

A series of novel 8-substituted dipyridodiazepinone-based inhibitors were investigated for their antiviral activity against wild type human immunodeficiency virus (HIV-1) and the clinically prevalent K103N/Y181C mutant virus. Our efforts have resulted in a series of benzoic acid analogues that are potent inhibitors of HIV-1 replication against a panel of HIV-1 strains resistant to non-nucleoside reverse transcriptase inhibitors (NNRTIs). Furthermore, the combination of good antiviral potency, a broad spectrum of activity, and an excellent pharmacokinetic profile provides strong justification for the further development of compound (7) as a potential treatment for wild type and NNRTI-resistant HIV-1 infection.

Animals↗

PubMed2005

Synthesis and evaluation of double-prodrugs against HIV. Conjugation of D4T with 6-benzyl-1-(ethoxymethyl)-5-isopropyluracil (MKC-442, emivirine)-type reverse transcriptase inhibitors via the SATE prodrug approach.

This paper reports the synthesis and the antiviral activities of new double-prodrugs against HIV based on the known mixed SATE (S-acyl-2-thioethyl) prodrug approach. The monophosphate of the nucleoside reverse transcriptase inhibitor (NRTI) d4T was masked with one SATE group and one aromatic group through which a nonnucleoside reverse transcriptase inhibitor (NNRTI) was linked. Double-prodrug 1 was a hybrid between d4T monophosphate and the known NNRTI MKC-442, which were linked through a labile p-hydroxybenzoyl protection group in the N-3 position of MKC-442. Double-prodrugs 2 and 3 were conjugates between d4T monophosphate and the new NNRTIs 15 and 19 linked through a stable phenolic linker that was a part of the N-1 substituents of the NNRTIs. The double-prodrugs 1, 2, and 3 all had good activities against wild-type HIV-1, Y181C mutant, and also against a HIV-2 strain that was resistant to NNRTIs.

Cell Line↗

PubMed1999

Altered pharmacokinetics of indinavir by a novel nonnucleoside reverse transcriptase inhibitor (HBY-097): a pharmacokinetic evaluation in HIV-positive patients.

HBY-097 (HBY), an investigational nonnucleoside reverse transcriptase inhibitor (NNRTI), and indinavir (IDV) share a common metabolic pathway, cytochrome P4503A4 (CYP3A4), and may clinically be used together as well as with zidovudine (ZDV). Thus, the potential pharmacokinetic (PK) interaction between these drugs was evaluated. HBY (500 mg Q8H), IDV (800 mg Q8H), and ZDV (200 mg Q8H) were given to 8 HIV-infected subjects. Serial plasma samples were collected at baseline (ZDV and IDV alone) and day 11 (all 3 drugs) to determine PK parameters using noncompartmental analysis. PK parameters for ZDV in the presence and absence of HBY were not appreciably different. However, both the maximum (Cmax) and minimum (Cmin) concentrations of IDV were significantly reduced, from a mean of 7514 +/- 1636 and 146 +/- 81 mcg/L to 4725 +/- 2494 mcg/L and 54 +/- 24 mcg/L (p < .05) after addition of HBY. Furthermore, apparent clearance (CL/F) of IDV before and after 11 days of concomitant HBY administration was significantly higher, from 0.69 +/- 0.14 to 1.94 +/- 0.63 L/h/kg (p < .05) with an associated reduction in area under the curve (AUC0-8) from 16,034 +/- 4903 to 6134 +/- 2701 mg/L/h (p < .05). The increase in IDV CL/F is consistent with the observed metabolic induction effects of other NNRTIs. The results of this trial showed that HBY significantly alters the pharmacokinetic parameters of IDV at the dose studied.

Adult↗

PubMed1999

Conformational study of the HIV-1 reverse transcriptase inhibitor 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine (HEPT).

The conformations of the HIV-1 reverse transcriptase inhibitor 1-[(2-hydroxyethoxy)methyl]-6-(phenylthio)thymine (HEPT) are calculated by semiempirical and mainly by ab initio methods in order to estimate the potential for the rotation around the carbon sulfur single bond. The results are compared to X-ray structures of HEPT associated to the HIV-1 reverse transcriptase. The NMR spectra of the compound are calculated to obtain some information about its structure in solution. The structure of HEPT in the complex is analysed to study the intermolecular interactions between the inhibitor and the surrounding protein, which determine the geometry of the inhibition complex.

Anti-HIV Agents↗

PubMed1992

High-performance liquid chromatographic procedure for the determination of a non-nucleoside HIV-1 reverse transcriptase inhibitor in human plasma.

A method for the determination of a non-nucleoside HIV-1 reverse transcriptase inhibitor in human plasma is described. Plasma samples are extracted using phenyl solid-phase extraction columns. The extract is analyzed by high-performance liquid chromatography with a polybutadiene-coated alumina column and a mobile phase of methanol-0.025 M pH 8 dibasic sodium phosphate buffer (1:1, v/v). Detection is based on ultraviolet absorbance at 326 nm. The assay was validated in the concentration range 10-500 ng/ml when 1-ml aliquots of plasma are extracted. The assay has been utilized to support human pharmacokinetic studies.

Administration, Oral↗

PubMed2003

Pharmacokinetic-pharmacodynamic analysis of lopinavir-ritonavir in combination with efavirenz and two nucleoside reverse transcriptase inhibitors in extensively pretreated human immunodeficiency virus-infected patients.

The steady-state pharmacokinetics and pharmacodynamics of two oral doses of lopinavir-ritonavir (lopinavir/r; 400/100 and 533/133 mg) twice daily (BID) when dosed in combination with efavirenz, plus two nucleoside reverse transcriptase inhibitors, were assessed in a phase II, open-label, randomized, parallel arm study in 57 multiple protease inhibitor-experienced but non-nucleoside reverse transcriptase inhibitor-naive human immunodeficiency virus (HIV)-infected subjects. All subjects began dosing of lopinavir/r at 400/100 mg BID; subjects in one arm increased the lopinavir/r dose to 533/133 mg BID on day 14. When codosed with efavirenz, the lopinavir/r 400/100 mg BID regimen resulted in lower lopinavir concentrations in plasma, particularly C(min), than were observed in previous studies of lopinavir/r administered without efavirenz. Increasing the lopinavir/r dose to 533/133 mg increased the lopinavir area under the concentration-time curve over a 12-h dosing interval (AUC(12)), C(predose), and C(min) by 46, 70, and 141%, respectively. The increase in lopinavir C(max) (33%,) did not reach statistical significance. Ritonavir AUC(12), C(max), C(predose), and C(min) values were increased 46 to 63%. The lopinavir predose concentrations achieved with the 533/133-mg BID dose were similar to those observed with lopinavir/r 400/100 mg BID in the absence of efavirenz. Results from univariate logistic regression analyses identified lopinavir and efavirenz inhibitory quotient (IQ) parameters, as well as the baseline lopinavir phenotypic susceptibility, as predictors of antiviral response (HIV RNA < 400 copies/ml at week 24); however, no lopinavir or efavirenz concentration parameter was identified as a predictor. Multiple stepwise logistic regressions confirmed the significance of the IQ parameters, as well as other baseline characteristics, in predicting virologic response at 24 weeks in this patient population.

Adult↗

PubMed2004

Capravirine, a nonnucleoside reverse-transcriptase inhibitor in patients infected with HIV-1: a phase 1 study.

Capravirine is a nonnucleoside reverse-transcriptase inhibitor (NNRTI) with a unique resistance profile. Although single mutations allow resistance to established NNRTIs, human immunodeficiency virus (HIV)-1 must undergo multiple mutations to achieve resistance to capravirine. In the present phase 1 study, capravirine was administered orally for up to 28 days to 55 HIV-1-infected individuals with CD4+ T lymphocyte counts of 50-500 cells/microL. The most frequent adverse events were diarrhea (5%) and nausea (4%), with no drug-related rashes observed. The day 15 median (mean) HIV-1 load decreased by 1.34 (1.45) log(10) copies/mL in the patients receiving 25 mg/kg/day. Capravirine demonstrated potent antiviral activity, even in antiretroviral-experienced patients.

Administration, Oral↗

PubMed2003

Toxic effects of nucleoside reverse transcriptase inhibitors on the liver. Value of electron microscopy analysis for the diagnosis of mitochondrial cytopathy.

Nucleoside reverse transcriptase inhibitors (NRTIs) induce mitochondrial toxic effects resulting in multiple organ disorders. Liver involvement has been associated mainly with severe lactic acidosis and massive steatosis. However, patients with HIV infection who are receiving antiretroviral treatment frequently have mildly abnormal liver test results that, to date, have not been linked unambiguously to the toxic effects of NRTIs. Thirteen patients with HIV infection treated with NRTI-based regimens had low-grade abnormal liver test results associated with digestive and nonspecific general symptoms. Histologic examination of liver samples showed diffuse steatosis in only 6 cases and mild steatosis in the remaining cases, associated with megamitochondria, mild lobular inflammation and necrosis, Mallory bodies, and perisinusoidal fibrosis. In all cases, ultrastructural study disclosed mitochondrial abnormalities. Our work demonstrates that NRTI-induced toxic effects in the liver may occur as indolent nonspecific disease with variable histologic features and emphasizes the diagnostic value of electron microscopy, particularly when diffuse steatosis is absent.

Adult↗

PubMed1993

Infectious amplification of wild-type human immunodeficiency virus from patients' lymphocytes and modulation by reverse transcriptase inhibitors in vitro.

The relative in vitro potency of nine human immunodeficiency virus (HIV) type 1 reverse transcriptase inhibitors was evaluated in a coculture assay which measures the frequencies of infectious primary cells from HIV-positive patients by the limiting dilution technique and measures their apparent reduction under increasing concentrations of drugs. An advantage of this assay is that it utilizes a variety of wild-type viruses not selected by in vitro propagation. Potency ranking placed the (-)-L-enantiomer of 2',3'-dideoxy-5-fluoro-3'-thiacytidine [(-)-FTC], an oxathiolane pyrimidine nucleoside analog (90% effective concentration = 55 nM), before 2',3'-dideoxycytidine (DDC) (74 nM), (-)-2',3'-dideoxy-3'-thiacytidine (3TC) (300 nM), 3'-azido-3'-deoxythymidine (AZT) (530 nM), TIBO R82913 (670 nM), and 2',3'-dideoxyinosine (DDI) (6,400 nM). HIV from AZT-naive patients' lymphocytes was more sensitive to the inhibitory effect of (-)-FTC, 3TC, or DDC than was highly AZT-resistant HIV obtained from AZT-treated patients' cells, indicating partial cross-resistance between thymidine and cytidine analogs. Combined inhibitory concentrations of AZT with (-)-FTC, 3TC, DDC, and DDI produced synergistic interactions as determined by the multiple-drug effect analysis. Synergistic interactions were demonstrable with AZT plus (-)-FTC or with AZT plus DDC with cells bearing AZT-resistant HIV. The inhibitory concentrations of AZT established by this cell-to-cell virus transmission assay are closer than those determined by the conventional assay system to the extracellular AZT concentrations required in patients' plasma to achieve comparable levels of HIV inhibition in vivo.

Acquired Immunodeficiency Syndrome↗

PubMed1997

Identification of the metabolites of the HIV-1 reverse transcriptase inhibitor delavirdine in monkeys.

Delavirdine mesylate (U-90152T) is a highly specific nonnucleoside HIV-1 reverse transcriptase inhibitor currently under development for the treatment of AIDS. The metabolism of delavirdine was investigated in male and female cynomolgus monkeys after oral administration of [14C-carboxamide]delavirdine mesylate at single doses of 80 mg/kg and multiple doses of 160 to 300 mg/kg/day. Desalkyl delavirdine was the major metabolite in circulation. In urine, desalkyl delavirdine accounted for nearly half of the radioactivity, with despyridinyl delavirdine and conjugates of desalkyl delavirdine accounting for most of the remaining radioactivity. Bile was mostly composed of desalkyl delavirdine and 6'-O-glucuronide delavirdine, with parent drug, 4-O-glucuronide delavirdine, and conjugates of desalkyl delavirdine as significant components. In addition, several minor metabolites were observed in urine and bile of delavirdine treated monkeys. The metabolism of delavirdine in the monkey was extensive and involved N-desalkylation, hydroxylation at the C-4' and C-6' positions of the pyridine ring, hydroxylation at the C-4 position of the indole ring, pyridine ring-cleavage, N-glucuronidation of the indole ring, and amide bond cleavage as determined by MS and/or one-dimensional and two-dimensional NMR spectroscopies. Phase II biotransformations included glucuronidation, sulfation, and beta-N-acetylglucosaminidation. The identification of the N-linked beta-N-acetylglucosamine and 4-O-glucuronide metabolites of delavirdine represents novel biotransformation pathways.

Animals↗

PubMed2003

Simultaneous separation of fifteen approved protease and reverse transcriptase inhibitors for human immunodeficiency virus therapy by capillary electrophoresis.

In the present investigation, a novel approach towards a complete separation of all 15 protease and reverse transcriptase inhibitors which are currently approved for use in highly active antiretroviral therapy in a single analytical run is presented. The developed method employs an acidic background electrolyte with sodium polyanethol sulfonate (SPAS) as polyanionic electroosmotic flow (EOF) modifier to establish a strong cathodic EOF, sodium dodecyl sulfate (SDS) as pseudostationary selector, and acetonitrile and ethanol as organic modifiers. Separation of the analytes is based on two different mechanisms. The more basic analytes are protonated at the prevailing pH conditions and thus migrate in front of the cathodic EOF, whereas the less basic and neutral analytes interact with the SDS and are retained after the EOF. By optimizing electrolyte pH, the amount of solvents and SDS concentrations in the background electrolyte it is possible to completely separate all compounds of interest.

Electrophoresis, Capillary↗

PubMed2006

Effects of trimethoprim on the clearance of apricitabine, a deoxycytidine analog reverse transcriptase inhibitor, and Lamivudine in the isolated perfused rat kidney.

Apricitabine (ATC) is a novel deoxycytidine analog reverse transcriptase inhibitor in development for the treatment of human immunodeficiency virus infection. Studies were performed to characterize the excretion of ATC and its metabolite, BCH-335 (-1-(2-hydroxymethyl-[1,3]oxathiolan-4-yl)-1H-pyrimidine-2,4-dione), in the isolated perfused rat kidney (IPK). A second objective was to investigate the effect of trimethoprim on ATC excretion because trimethoprim inhibits the excretion of lamivudine, structurally similar to ATC, in the IPK. ATC excretion was nonlinear at doses of 80 to 1600 microg. The excretion ratio (ratio of clearance to glomerular filtration rate, assuming negligible protein binding) was greater than 1.0, indicating net tubular secretion. In contrast, the excretion of BCH-335 was independent of the dose of BCH-335. Concomitant administration of ATC and BCH-335 did not affect the excretion of either compound. Trimethoprim significantly inhibited the excretion of both ATC and BCH-335, with IC(50) values of 0.45 and 0.54 microg/ml, respectively. In the presence of trimethoprim, the excretion ratios for both compounds were less than 1.0, indicating tubular reabsorption. Trimethoprim inhibited the excretion of ATC and lamivudine to similar extents. Following concomitant administration of ATC, lamivudine, and trimethoprim, there was no evidence of an interaction between ATC and lamivudine. These results suggest that ATC undergoes active tubular secretion in the kidney. Because the renal excretion of both ATC and lamivudine is inhibited by trimethoprim to similar extents, in clinical practice exposure to ATC, it would be expected to be increased in the presence of therapeutic concentrations of trimethoprim to a similar extent as has been shown previously for lamivudine.

Animals↗

PubMed1997

Metabolism of the HIV-1 reverse transcriptase inhibitor delavirdine in mice.

Delavirdine mesylate (U-90152T) is a highly specific nonnucleoside HIV-1 reverse transcriptase inhibitor currently under development for the treatment of AIDS. The excretion, disposition, brain penetration, and metabolism of delavirdine were investigated in CD-1 mice after oral administration of [14C]delavirdine mesylate at single doses of 10 and/or 250 mg/kg and multiple doses of 200 mg/kg/day. Studies were conducted with 14C-carboxamide and 2-14C-pyridine labels, as well as 13C3-labeled drug to facilitate metabolite identification. Excretion was dose dependent with 57-70% of the radioactivity eliminated in feces and 25-36% in urine. Pharmacokinetic analyses of delavirdine and its N-desisopropyl metabolite (desalkyl delavirdine) in plasma showed that delavirdine was absorbed and metabolized rapidly, that it constituted a minor component in circulation, that its pharmacokinetics were nonlinear, and that its metabolism to desalkyl delavirdine was capacity limited or inhibitable. Delavirdine did not significantly cross the blood-brain barrier; however, its N-isopropylpyridinepiperazine metabolite arising from amide bond cleavage-was present in brain at levels 2- to 3-fold higher than in plasma. The metabolism of delavirdine in the mouse was extensive and involved amide bond cleavage, N-desalkylation, hydroxylation at the C-6' position of the pyridine ring, and pyridine ring-cleavage as determined by MS and/or 1H and 13C NMR spectroscopies. N-desalkylation and amide bond cleavage were the primary metabolic pathways at low drug doses and, as the biotransformation of delavirdine to desalkyl delavirdine reached saturation or inhibition, amide bond cleavage became the predominant pathway at higher doses and after multiple doses.

Animals↗

PubMed2004

Docking-based CoMFA and CoMSIA studies of non-nucleoside reverse transcriptase inhibitors of the pyridinone derivative type.

Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) were performed on a set of pyridinone derivatives. A molecular alignment obtained by docking of compounds into the non-nucleoside reverse transcriptase inhibitor binding site of HIV-1 was used. Good correlations between the calculated binding free energies and experimental inhibitory activities suggest that the binding conformations of these inhibitors are reasonable. Robust and predictive 3D-QSAR models were obtained with q2 values of 0.706 and 0.723 for CoMFA and CoMSIA, respectively. The models were validated by an external test set obtaining r2 pred values of 0.720 and 0.750 for CoMFA and CoMSIA, respectively. The CoMFA, CoMSIA and docking results help to understand the type of interactions that occur between pyridinone derivatives with the non-nucleoside reverse transcriptase inhibitor binding pocket, and explain the viral resistance to pyridinone derivatives upon mutation of amino acids Tyr181 and Tyr188. The results obtained provide information for a better understanding of the drug resistant mechanisms. The 3D-QSAR models derived will be used to guide the design of pyridinone derivatives active against mutant strains of reverse transcriptase.

Computer Simulation↗

PubMed2001

Phenotypic and genotypic resistance to nucleoside reverse transcriptase inhibitors in HIV-1 clinical isolates.

OBJECTIVE: To assess phenotypic and genotypic cross-resistance to nucleoside reverse transcriptase inhibitors in patients treated with a combination including zidovudine, who were switched to a combination including stavudine. METHODS: We analysed 24 clinical HIV-1 isolates from 12 patients before and several months after therapeutic switching. Plasma HIV-1 RNA was measured using quantitative polymerase chain reaction (Roche). Genotypic resistance was measured by sequencing the reverse transcriptase gene from plasma HIV-1 RNA. Phenotypic resistance was measured using a recombinant assay (Virco). RESULTS: Patients were treated with a combination including zidovudine for a mean (+/- SEM) period of 21.8 +/- 3.5 months and had a plasma viral load of 4.1 +/- 0.2 log HIV-1 RNA copies/mL (time 1). After a mean period of 19.3 +/- 1.6 months following the therapeutic change, the plasma viral load was 3.6 +/- 0.1 log copies/mL (time 2). At time 1, genotypic resistance to zidovudine was found in all cases (41L: four cases; 41L, 215Y: five cases; 41L, 210W, 215Y: two cases; K70R: one case) with a mean 6.6 +/- 1.6-fold increase in the median inhibitory concentration (IC50) to zidovudine and 1.7 +/- 0.4-fold to stavudine. At time 2, genotypic resistance to zidovudine was found in 11 out of 12 cases (41L: two cases; 41L, 215Y: six cases; 41L, 210W, 215Y: two cases; M41L, D67N, L210W, T215Y: one case) with a mean 18.9 +/- 8.8-fold increase in the IC50 to zidovudine and 1.4 +/- 0.4-fold to stavudine CONCLUSIONS: In this clinical series of patients with suboptimal control of plasma HIV-1 RNA using a combination including zidovudine, the presence of zidovudine-related mutations was associated with a decreased phenotypic sensitivity to this drug. Despite persistent HIV-1 replication, switching to stavudine was associated with a further decrease in phenotypic sensitivity to zidovudine but not to stavudine after 19 months. These data suggest that stavudine remains a possible option in zidovudine-experienced patients.

Adult↗

PubMed2004

Action of anti-HIV drugs and resistance: reverse transcriptase inhibitors and protease inhibitors.

Currently, 20 drugs have been approved for Human Immunodeficiency Virus type-1 (HIV-1) clinical therapy. These drugs inhibit HIV-1 reverse transcriptase, protease, or virus entry. Introduction of a combination therapy with reverse transcriptase inhibitors and protease inhibitors has resulted in a drastic decrease in HIV-1 related mortality. Although the combination therapy can suppress viral replication below detection levels in current available assays, low levels of on-going viral replication still persist in some patients. Long-term administration of the combination therapy may increase selective pressure against viruses, and subsequently induce emergence of multiple drug-resistant HIV-1 variants. Attempts have been made to design novel antiretroviral drugs that would be able to suppress replication of the resistant variants. At present, several investigational drugs are being tested in clinical trials. These drugs target not only the resistant variants, but also improvement in oral bioavilability or other viral proteins such as HIV-1 integrase, ribonuclease H, and HIV-1 entry (CD4 attachment inhibitors, chemokine receptors antagonists, and fusion inhibitors). Understanding mechanism(s) of action of the drugs and mechanisms of drug resistance is necessary for successful designs in the next generation of anti-HIV-1 drugs. In this review, the mechanisms of action of reverse transcriptase- and protease-inhibitors, and the mechanism of resistance to these inhibitors, are described.

Animals↗

PubMed2002

Differential modulation of P-glycoprotein expression and activity by non-nucleoside HIV-1 reverse transcriptase inhibitors in cell culture.

PURPOSE: This study investigated the effects of the non-nucleoside HIV-1 reverse transcriptase inhibitors (NNRTI) nevirapine (NVR), efavirenz (EFV), and delavirdine (DLV) on P-glycoprotein (P-gp) activity and expression to anticipate P-gp related drug-drug interactions associated with combination therapy. METHODS: NNRTIs were evaluated as P-gp substrates by measuring differential transport across Caco-2 cell monolayers. Inhibition of P-gp mediated rhodaminel23 (Rh123) transport in Caco-2 cells was used to assess P-gp inhibition by NNRTIs. Induction of P-gp expression and activity in LS180V cells following 3-day exposure to NNRTIs was measured by western blot analysis and cellular Rh123 uptake, respectively. RESULTS: The NNRTIs showed no differential transport between the basolateral to apical and apical to basolateral direction. NNRTI transport in either direction was not affected by the P-gp inhibitor verapamil. DLV inhibited Rh123 transport, causing a reduction to 15% of control at 100 microM (IC50 = 30 microM). NVR caused a concentration-dependent induction of P-gp expression in LS180V cells resulting in a 3.5-fold increase in immunoreactive P-gp at 100 microM NVR. Induction attributable to EFV and DLV was quantitatively smaller. NVR significantly reduced cellular uptake of Rh123 into LS180V cells, indicating increased drug efflux due to induced P-gp activity; effects of EFV and DLV were smaller. Acute DLV treatment of LS180V cells previously induced with NVR or ritonavir did not reverse the decreased Rh123 cell accumulation. CONCLUSIONS: NNRTIs show differential effects on P-gp activity and expression in vitro. Clinical studies are required to elucidate the clinical importance of potential drug interactions.

ATP Binding Cassette Transporter, Subfamily B, Mem↗