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Dooley K.E.,Johns Hopkins University | Park J.-G.,Harvard University | Swindells S.,University of Nebraska Medical Center | Allen R.,AIDS Clinical Trials Group Operations | And 8 more authors.
Journal of Acquired Immune Deficiency Syndromes | Year: 2012

Background: Drug-drug interactions complicate management of coinfection with HIV-1 and Mycobacterium tuberculosis. Bedaquiline (formerly TMC207), an investigational agent for the treatment of tuberculosis, is metabolized by cytochrome P450 (CYP) 3A which may be induced by the antiretroviral drug efavirenz. Methods: This was a phase 1 pharmacokinetic drug interaction trial. Each healthy volunteer received two 400 mg doses of bedaquiline, the first alone and the second with concomitant steady-state efavirenz. Plasma pharmacokinetic sampling for bedaquiline and its N-monodesmethyl metabolite was performed over 14 days after each bedaquiline dose. Steady-state efavirenz pharmacokinetics were also determined. Efavirenz metabolizer status was based on CYP2B6 composite 516/983 genotype. Results: Thirty-three of 37 enrolled subjects completed the study. Geometric mean of ratios for bedaquiline with efavirenz versus bedaquiline alone were 0.82 [90% confidence interval (CI): 0.75 to 0.89] for the 14-day area under the concentration-time curve (AUC 0-336 h) and 1.00 (90% CI: 0.88 to 1.13) for the maximum concentration (C max). For N-monodesmethyl metabolite, the geometric mean of ratios was 1.07 (90% CI: 0.97 to 1.19) for AUC 0-336 h and 1.89 (90% CI: 1.66 to 2.15) for C max. There were no grade 3 or 4 clinical adverse events. One subject developed asymptomatic grade 3 serum transaminase elevation, prompting study drug discontinuation. Efavirenz concentrations stratified by CYP2B6 genotype were similar to historical data. Conclusions: Single-dose bedaquiline was well tolerated alone and with steady-state efavirenz. The effect of efavirenz on bedaquiline concentrations is unlikely to be clinically significant. © 2012 Lippincott Williams &Wilkins.

Zeuzem S.,Goethe University Frankfurt | Andreone P.,University of Bologna | Pol S.,University of Paris Descartes | Lawitz E.,Alamo Medical Research | And 18 more authors.
New England Journal of Medicine | Year: 2011

BACKGROUND: Up to 60% of patients with hepatitis C virus (HCV) genotype 1 infection do not have a sustained virologic response to therapy with peginterferon alfa plus ribavirin. METHODS: In this randomized, phase 3 trial, we evaluated the addition of telaprevir to peginterferon alfa-2a plus ribavirin in patients with HCV genotype 1 infection who had no response or a partial response to previous therapy or who had a relapse after an initial response. A total of 663 patients were assigned to one of three groups: the T12PR48 group, which received telaprevir for 12 weeks and peginterferon plus ribavirin for a total of 48 weeks; the lead-in T12PR48 group, which received 4 weeks of peginterferon plus ribavirin followed by 12 weeks of telaprevir and peginterferon plus ribavirin for a total of 48 weeks; and the control group (PR48), which received peginterferon plus ribavirin for 48 weeks. The primary end point was the rate of sustained virologic response, which was defined as undetectable HCV RNA 24 weeks after the last planned dose of a study drug. RESULTS: Rates of sustained virologic response were significantly higher in the two telaprevir groups than in the control group among patients who had a previous relapse (83% in the T12PR48 group, 88% in the lead-in T12PR48 group, and 24% in the PR48 group), a partial response (59%, 54%, and 15%, respectively), and no response (29%, 33%, and 5%, respectively) (P<0.001 for all comparisons). Grade 3 adverse events (mainly anemia, neutropenia, and leukopenia) were more frequent in the telaprevir groups than in the control group (37% vs. 22%). CONCLUSIONS: Telaprevir combined with peginterferon plus ribavirin significantly improved rates of sustained virologic response in patients with previously treated HCV infection, regardless of whether there was a lead-in phase. (Funded by Tibotec and Vertex Pharmaceuticals; REALIZE ClinicalTrials.gov number, NCT00703118.) Copyright © 2011 Massachusetts Medical Society.

Cohen C.J.,Community Research Initiative of New England | Andrade-Villanueva J.,University of Guadalajara | Clotet B.,Autonomous University of Barcelona | Fourie J.,Dr urie Medical Center | And 8 more authors.
The Lancet | Year: 2011

Background The non-nucleoside reverse transcriptase inhibitor (NNRTI), rilpivirine (TMC278; Tibotec Pharmaceuticals, County Cork, Ireland), had equivalent sustained efficacy to efavirenz in a phase 2b trial in treatment-naive patients infected with HIV-1, but fewer adverse events. We aimed to assess non-inferiority of rilpivirine to efavirenz in a phase 3 trial with common background nucleoside or nucleotide reverse transcriptase inhibitors (N[t]RTIs). Methods We undertook a 96-week, phase 3, randomised, double-blind, double-dummy, non-inferiority trial in 98 hospitals or medical centres in 21 countries. We enrolled adults (≥18 years) not previously given antiretroviral therapy and with a screening plasma viral load of 5000 copies per mL or more and viral sensitivity to background N(t)RTIs. We randomly allocated patients (1:1) using a computer-generated interactive web-response system to receive oral rilpivirine 25 mg once daily or efavirenz 600 mg once daily; all patients received an investigator-selected regimen of background N(t)RTIs (tenofovir-disoproxil-fumarate plus emtricitabine, zidovudine plus lamivudine, or abacavir plus lamivudine). The primary outcome was non-inferiority (12 margin on logistic regression analysis) at 48 weeks in terms of confirmed response (viral load <50 copies per mL, defined by the intent-to-treat time to loss of virologic response [TLOVR] algorithm) in all patients who received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT00543725. Findings From May 22, 2008, we screened 947 patients and enrolled 340 to each group. 86 of patients (291 of 340) who received at least one dose of rilpivirine responded, compared with 82 of patients (276 of 338) who received at least one dose of efavirenz (difference 3·5 [95 CI -1·7 to 8·8]; pnon-inferiority<0·0001). Increases in CD4 cell counts were much the same between groups. 7 of patients (24 of 340) receiving rilpivirine had a virological failure compared with 5 of patients (18 of 338) receiving efavirenz. 4 of patients (15) in the rilpivirine group and 7 (25) in the efavirenz group discontinued treatment due to adverse events. Grade 2-4 treatment-related adverse events were less common with rilpivirine (16 [54 patients]) than they were with efavirenz (31 [104]; p<0·0001), as were rash and dizziness (p<0·0001 for both) and increases in lipid levels were significantly lower with rilpivirine than they were with efavirenz (p<0·0001). Interpretation Despite a slightly increased incidence of virological failures, a favourable safety profile and non-inferior efficacy compared with efavirenz means that rilpivirine could be a new treatment option for treatment-naive patients infected with HIV-1. Funding Tibotec. © 2011 Elsevier Ltd.

Horsburgh Jr. C.R.,Boston University | Haxaire-Theeuwes M.,Tibotec | Lienhardt C.,World Health Organization | Wingfield C.,PATH | And 4 more authors.
International Journal of Tuberculosis and Lung Disease | Year: 2013

Several new classes of anti-tuberculosis agents are likely to become available in the coming decade. Ensuring prompt access to these drugs for patients without other treatment options is an important medical and public health issue. This article reviews the current state of 'compassionate use' and 'expanded access' programs for these new drugs, and identifies several shortcomings that will limit patient access to the drugs. A series of five steps is outlined that will need to be taken by national health bodies, international agencies and non-governmental organizations to prevent undue delays in access to new tuberculosis drugs for patients who could benefit from them. Following these steps can ensure that patients will be able to benefit from access to these drugs, while minimizing the risk of emergence of resistance to the drug. © 2012 The Union.

Moreno C.,Free University of Colombia | Berg T.,University of Leipzig | Tanwandee T.,Mahidol University | Thongsawat S.,Chiang Mai University | And 6 more authors.
Journal of Hepatology | Year: 2012

Background & Aims: TMC435 is an investigational, once-daily, oral NS3/4A protease inhibitor currently in phase III development for the treatment of hepatitis C virus (HCV) infection. Phase I and II studies in patients infected with HCV genotype 1 have demonstrated that TMC435 is generally well tolerated, has a pharmacokinetic profile that supports once daily dosing, and demonstrates potent antiviral activity. This phase IIa study (TMC435-C202; NCT00812331) was conducted to investigate the antiviral activity, safety, tolerability, and pharmacokinetics of TMC435 in treatment-nave patients infected with HCV genotypes 2-6. Methods: The study consisted of 7 days of monotherapy with TMC435 (200 mg once daily). Patients could begin treatment with pegylated interferon/ribavirin from day 8 with a follow-up period up to days 37-42. Results: Thirty-seven patients were enrolled in Germany, Belgium and Thailand. For the primary end point at day 8, the mean (± standard error) change in plasma HCV ribonucleic acid (log 10 IU/ml) from baseline was the greatest for genotypes 6 (-4.35 ± 0.29) and 4 (-3.52 ± 0.43), followed by genotypes 2 (-2.73 ± 0.71) and 5 (-2.19 ± 0.39). No antiviral activity was evident for genotype 3. Viral breakthrough occurred in six patients during the monotherapy phase and in six additional patients during PegIFN/RBV-only period. All adverse events were mild or moderate and there were no discontinuations during the TMC435 monotherapy period. Conclusions: The results of this phase IIa proof-of-concept trial provide evidence that TMC435 has a spectrum of activity against multiple HCV genotypes, except for genotype 3. In this study, TMC435 was generally safe and well tolerated. © 2012 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Nelson M.,Chelsea and Westminster Hospital | Girard P.-M.,Hopital Saint Antoine | Girard P.-M.,University Pierre and Marie Curie | Girard P.-M.,French Institute of Health and Medical Research | And 5 more authors.
Journal of Antimicrobial Chemotherapy | Year: 2010

Objectives: To examine how treatment adherence differences in ARTEMIS (96 week analysis) affected clinical outcome, and to assess factors impacting adherence. Patients and methods: ARTEMIS is a Phase III trial, in HIV-1-infected treatment-naive patients, comparing efficacy and safety of once-daily darunavir/ritonavir (800/100 mg) versus lopinavir/ritonavir (800/200 mg total daily dose), each with a fixed-dose background tenofovir and emtricitabine regimen. Self-reported treatment adherence was assessed using the Modified Medication Adherence Self-Report Inventory (M-MASRI). In posthoc analyses, mean adherence from weeks 4-96 was used to assess overall adherence for each patient, and transformed into a binary variable (.95%,adherent; ≤95%,suboptimally adherent). Results: Overall adherence was high: 83% of darunavir/ritonavir-treated patients and 78% of lopinavir/ritonavirtreated patients were .95%adherent. The difference in virological response rate for adherent versus suboptimally adherent patients was smaller for darunavir/ritonavir (6%difference: 82%versus 76%, P=0.3312) than for lopinavir/ritonavir (25% difference: 78% versus 53%, P,0.0001). In suboptimally adherent patients, a higher virological response rate was seen with darunavir/ritonavir (76%) versus lopinavir/ritonavir (53%) (P,0.01). Suboptimally adherent patients (both treatment groups) reported more adverse events (AEs), including gastrointestinal AEs, than adherent patients. Darunavir/ritonavir had a lower rate of AEs, including gastrointestinal AEs, than lopinavir/ritonavir, in adherent and suboptimally adherent patients. Conclusions: Suboptimal adherence had no significant effect on the virological response rate with once-daily darunavir/ritonavir treatment. In contrast, the lopinavir/ritonavir response rate was significantly reduced in suboptimally adherent patients compared with adherent patients. Once-daily darunavir/ritonavir resulted in a higher virological response rate in suboptimally adherent patients compared with lopinavir/ritonavir. © The Author 2010.

Roymans D.,Tibotec BVBA | De Bondt H.L.,Tibotec BVBA | Arnoult E.,Tibotec | Geluykens P.,Tibotec BVBA | And 10 more authors.
Proceedings of the National Academy of Sciences of the United States of America | Year: 2010

Six-helix bundle (6HB) formation is an essential step for many viruses that rely on a class I fusion protein to enter a target cell and initiate replication. Because the binding modes of small molecule inhibitors of 6HB formation are largely unknown, precisely how they disrupt 6HB formation remains unclear, and structure-based design of improved inhibitors is thus seriously hampered. Here we present the high resolution crystal structure of TMC353121, a potent inhibitor of respiratory syncytial virus (RSV), bound at a hydrophobic pocket of the 6HB formed by amino acid residues from both HR1 and HR2 heptad-repeats. Binding of TMC353121 stabilizes the interaction of HR1 and HR2 in an alternate conformation of the 6HB, in which direct binding interactions are formed between TMC353121 and both HR1 and HR2. Rather than completely preventing 6HB formation, our data indicate that TMC353121 inhibits fusion by causing a local disturbance of the natural 6HB conformation.

Rimsky L.,Tibotec BVBA | Vingerhoets J.,Tibotec BVBA | Van Eygen V.,Tibotec BVBA | Eron J.,University of North Carolina at Chapel Hill | And 4 more authors.
Journal of Acquired Immune Deficiency Syndromes | Year: 2012

Genotypic and phenotypic characterization was performed of HIV-1 isolates from treatment-naive HIV-1-infected patients experiencing virologic failure (VF) during treatment with the nonnucleoside reverse transcriptase inhibitor (NNRTIs) rilpivirine or efavirenz in the pooled phase 3 studies ECHO and THRIVE. Among 686 patients receiving rilpivirine, 72 (10%) experienced VF versus 39 of 682 (6%) receiving efavirenz. In patients with low baseline viral load (VL) ≤100,000 copies per milliliter, the proportions of rilpivirine VFs (19 of 368) and efavirenz VFs (16 of 330) were the same (5%). In patients with high baseline VL >100,000 copies per milliliter, the proportion of VFs was higher with rilpivirine (53 of 318; 17%) than efavirenz (23 of 352; 7%). The rate of rilpivirine VF was comparable between HIV-1 subtype B-infected (11%) and nonsubtype B-infected (8%) patients. The absolute number of VFs with treatment-emergent NNRTI resistance-associated mutations (RAMs) was higher for rilpivirine (most commonly E138K or K101E) than efavirenz (most commonly K103N), but relative proportions were similar [63% (39 of 62) vs. 54% (15 of 28), respectively]. More rilpivirine VFs had treatment-emergent nucleoside/nucleotide reverse transcriptase inhibitor RAMs than efavirenz VFs [68% (42 of 62) versus 32% (9 of 28), respectively], most commonly M184I and M184V. The proportion of rilpivirine VFs with RAMs in patients with low baseline VL was lower than in those with high baseline VL [38% (6 of 16) versus 72% (33 of 46) for NNRTI RAMs and 44% (7 of 16) versus 76% (35 of 46) for nucleoside/nucleotide reverse transcriptase inhibitor RAMs, respectively]. In summary, VF and treatment-emergent reverse transcriptase RAMs were similar at low baseline VL but more frequent at high baseline VL in rilpivirine-treated than in efavirenz-treated patients. The frequent emergence of E138K, especially in combination with M184I, in rilpivirine VFs is a unique finding of these trials.

Alonso A.,Hasselt University | Laenen A.,Hasselt University | Molenberghs G.,Hasselt University | Molenberghs G.,Catholic University of Leuven | And 2 more authors.
Biometrics | Year: 2010

The reliability of multi-item scales has received a lot of attention in the psychometric literature, where a myriad of measures like the Cronbach's α or the Spearman-Brown formula have been proposed. Most of these measures, however, are based on very restrictive models that apply only to unidimensional instruments. In this article, we introduce two measures to quantify the reliability of multi-item scales based on a more general model. We show that they capture two different aspects of the reliability problem and satisfy a minimum set of intuitive properties. The relevance and complementary value of the measures is studied and earlier approaches are placed in a broader theoretical framework. Finally, we apply them to investigate the reliability of the Positive and Negative Syndrome Scale, a rating scale for the assessment of the severity of schizophrenia. © 2010, The International Biometric Society.

Hohlfeld K.,University of Southampton | Tomassi C.,University of Southampton | Wegner J.K.,Tibotec | Kesteleyn B.,Tibotec | Linclau B.,University of Southampton
ACS Medicinal Chemistry Letters | Year: 2011

A series of darunavir analogues featuring a substituted bis-THF ring as P2 ligand have been synthesized and evaluated. High affinity protease inhibitors (PIs) with an interesting activity on wild-type HIV and a panel of multi-PI resistant HIV-1 mutants containing clinically observed, primary mutations were identified using a cell-based assay. A number of PIs have been synthesized that show equivalent and greater activity for HIV-1 mutant strains as compared to wild-type HIV-1. The activity on the purified enzyme was confirmed for a selection of analogues. © 2011 American Chemical Society.

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