RESUMEN
The objective of this study was to support posaconazole dose regimens in pediatric patients aged ≥2 years, using a population pharmacokinetic (PK) approach with data from a phase 1b study (NCT02452034). A one-compartment model with first-order absorption was fit to pharmacokinetic data from 144 participants aged 2 to 17 years, who were administered posaconazole as intravenous (IV) and powder for oral suspension (PFS) formulations, or IV only, at dosing regimens of 3.5, 4.5, and 6 mg/kg. The influence of demographic and clinical factors on pharmacokinetic parameters was evaluated using a stepwise forward inclusion/backward exclusion procedure. The final model simulated posaconazole exposure in patients aged 2 to <7 and 7 to 17 years at dosing regimens of 4.5, 6, and 7.5 mg/kg. Plasma concentration data following IV and PFS administration were well-described by a one-compartment model with first-order absorption and estimated bioavailability, where clearance and volume were subject to allometric scaling by body weight. The 6-mg/kg dosing regimen achieved the pharmacokinetic target (90% of the pediatric population having an average steady-state plasma concentration of ≥500 and <2,000 ng/mL) for both age groups, regardless of whether patients received IV and PFS or IV only. In a virtual adolescent population (body weight >40 kg), the 300 mg/day posaconazole tablet was also predicted to achieve the pharmacokinetic target and remain within a safe range of exposure. These data informed a weight-based nomogram for PFS dosing to maximize the number of pediatric patients achieving the pharmacokinetic target across weight bands, while also maintaining a favorable benefit/risk profile.
Asunto(s)
Antifúngicos , Neutropenia , Triazoles , Adolescente , Niño , Humanos , Administración Oral , Peso Corporal , Neutropenia/inducido químicamente , Polvos , PreescolarRESUMEN
BACKGROUND AND OBJECTIVE: A double-blind phase 3 study was conducted to compare posaconazole 300 mg intravenously (IV)/300 mg orally once daily (twice daily day 1) with voriconazole 4 mg/kg IV twice daily/200 mg orally twice daily (6 mg/kg day 1) for treatment of invasive aspergillosis. This analysis was conducted to summarize the pharmacokinetics and exposure-response relationships of posaconazole and voriconazole using plasma trough concentration (Ctrough) as a surrogate for exposure from the double-blind phase 3 study. METHODS: The pharmacokinetic evaluable population included all intention-to-treat (ITT) participants with at least one plasma concentration during the treatment period. Treatment blinding was maintained without therapeutic drug monitoring. Ctrough sampling occurred throughout treatment; efficacy and safety were evaluated using quartiles determined by mean Ctrough concentrations. Exposure efficacy variables included day 42 all-cause mortality (primary study endpoint) and global clinical response. Exposure safety variables included all adverse events and treatment-related adverse events. RESULTS: The pharmacokinetic analysis population included 506 of 575 ITT participants (437 with Ctrough concentrations: 228 posaconazole, 209 voriconazole). No trend was seen across quartiles of posaconazole Ctrough for the key efficacy endpoint of all-cause mortality through day 42. Participants in the highest quartile of voriconazole Ctrough had higher all-cause mortality through day 42 than participants in the lower three quartiles of voriconazole Ctrough. Similar findings were observed for global clinical response and Ctrough. No clear exposure safety trend by quartile was seen for posaconazole or voriconazole. CONCLUSIONS: A strong exposure-response relationship was not observed across the range of exposure from the administered doses and formulations for posaconazole or voriconazole. TRIAL REGISTRATION: NCT01782131; registered January 30, 2013.
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Aspergilosis , Triazoles , Humanos , Voriconazol/efectos adversos , Triazoles/efectos adversos , Aspergilosis/tratamiento farmacológico , Método Doble CiegoRESUMEN
BACKGROUND: Therapies to prevent recurrence of Clostridioides difficile infection (CDI) in pediatric patients are needed. Bezlotoxumab is a fully human monoclonal antibody approved for prevention of recurrent CDI in adults. We assessed the pharmacokinetics, safety, tolerability, and efficacy of bezlotoxumab in pediatric patients. METHODS: MODIFY III was a multicenter, double-blind, placebo-controlled study of bezlotoxumab in children (1 to <18 years) receiving antibacterial treatment for CDI. Participants were randomized 3:1 to receive a single infusion of bezlotoxumab (10 mg/kg) or placebo and were stratified by age at randomization (cohort 1: 12 to <18 years, cohort 2: 1 to <12 years). The primary objective was to characterize bezlotoxumab pharmacokinetics to support dose selection for pediatric patients; the primary endpoint was the area under the bezlotoxumab serum concentration-time curve (AUC0-inf). Safety, tolerability, and efficacy were monitored for 12 weeks post-infusion. RESULTS: A total of 148 participants were randomized and 143 were treated: 107 with bezlotoxumab and 36 with placebo (cohort 1 n = 60, cohort 2 n = 83; median age 9.0 years); 52.4% of participants were male and 80.4% were white. Geometric mean ratios (90% CI) for bezlotoxumab AUC0-inf were 1.06 (0.95, 1.18) and 0.82 (0.75, 0.89) h * µg/mL for cohorts 1 and 2, respectively. Bezlotoxumab 10 mg/kg was generally well-tolerated with an adverse event profile similar to placebo, including no treatment discontinuations due to adverse events. CDI recurrence was low and comparable for bezlotoxumab (11.2%) and placebo (14.7%). CONCLUSIONS: The results of this study support the bezlotoxumab dose of 10 mg/kg for pediatric patients. TRIAL REGISTRATION: NCT03182907 at ClinicalTrials.gov.
Asunto(s)
Antibacterianos , Infecciones por Clostridium , Adulto , Humanos , Niño , Masculino , Femenino , Método Doble Ciego , Antibacterianos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Infecciones por Clostridium/tratamiento farmacológicoRESUMEN
BACKGROUND: Second generation triazoles including posaconazole are efficacious for prophylaxis and salvage treatment of life-threatening invasive fungal diseases but have been associated with hepatic adverse events (AEs). This report evaluated hepatic AEs in posaconazole-treated patients. RESEARCH DESIGN AND METHODS: Hepatobiliary AEs occurring after posaconazole exposure in the company's global safety database were analyzed to characterize underlying medical conditions and concomitant drug exposure. RESULTS: As of October 2019, 516 cases (168 from clinical trials, 348 from postmarketing use) containing 618 hepatobiliary AEs were reported regardless of causality. Frequently reported terms were hyperbilirubinemia, hepatic failure, and hepatic function abnormal (clinical trial reports) and hepatotoxicity, hepatocellular injury, and hepatic function abnormal (postmarketing reports). Cases reporting concurrent medications associated with drug-induced liver injury (DILI) included 8% with verified severe DILI (vMost-DILI) concern, 24% with verified mild to moderate DILI (vLess-DILI) concern, and 37% received both vMost-DILI and vLess-DILI-concern medications in the DILIrank data set. CONCLUSIONS: Use of concomitant medications with known risks for hepatic injury appears to be an important contributor for the development of hepatotoxicity in patients treated with posaconazole.
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Enfermedad Hepática Inducida por Sustancias y Drogas , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Infecciones Fúngicas Invasoras , Antifúngicos/efectos adversos , Enfermedad Hepática Inducida por Sustancias y Drogas/epidemiología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Humanos , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Triazoles/efectos adversosRESUMEN
BACKGROUND: Voriconazole has been recommended as primary treatment for patients with invasive aspergillosis. Intravenous and tablet formulations of posaconazole that have improved systemic absorption could be an effective alternative to voriconazole. We aimed to assess non-inferiority of posaconazole to voriconazole for the primary treatment of invasive aspergillosis. METHODS: We did a randomised, prospective, double-blind, double-dummy, controlled trial comparing posaconazole (intravenous or oral posaconazole 300 mg twice on day 1, followed by 300 mg once a day for days 2-84) with voriconazole (6 mg/kg intravenous or 300 mg oral twice on day 1 followed by 4 mg/kg intravenously or 200 mg orally twice a day for days 2-84) for 12 weeks or less in the primary treatment of invasive aspergillosis. Participants were from 91 study sites in 26 countries, were aged 13 years or older, weighed at least 40 kg, and met criteria for proven, probable, or possible fungal disease. Participants were randomly assigned (1:1) via a computer-generated randomisation schedule with stratification by risk status. The primary endpoint was cumulative all-cause mortality up until day 42 in the intention-to-treat (ITT) population (defined as randomly assigned participants who received ≥1 dose of study drug), with a 10% non-inferiority margin. The ITT population was also evaluated for safety. This study is registered with ClinicalTrials.gov, NCT01782131, and EudraCT, 2011-003938-14. FINDINGS: Between Oct 25, 2013, and Sept 10, 2019, of 653 individuals assessed for eligibility, 575 ITT participants were randomly assigned and received one or more doses of study drug (n=288 [50%] posaconazole, n=287 [50%] voriconazole). Mortality up until day 42 was 15% (44 of 288) in the posaconazole group and 21% (59 of 287) in the voriconazole group (treatment difference -5·3% [95% CI -11·6 to 1·0]; p<0·0001). Mortality up until day 42 in the full-analysis-set subpopulation (ITT participants with proven or probable invasive aspergillosis) supported this conclusion: 31 (19%) of 163 participants in the posaconazole group and 32 (19%) of 171 participants in the voriconazole group (treatment difference 0·3% [95% CI -8·2 to 8·8]). The most frequently reported treatment-related adverse events (incidence >3%) were increased aspartate aminotransferase (AST) or alanine aminotransferase (ALT), nausea, hypokalaemia, and vomiting in the posaconazole group and increased ALT, AST, or alkaline phosphatase, hallucination, increased γ-glutamyltransferase peptidase, nausea, and blurred vision in the voriconazole group. The overall incidence of treatment-related adverse event rates in the ITT population was 30% for posaconazole and 40% for voriconazole (treatment difference -10·2% [95% CI -17·9 to -2·4]). INTERPRETATION: Posaconazole was non-inferior to voriconazole for all-cause mortality up until day 42 in participants with invasive aspergillosis. Posaconazole was well tolerated, and participants had fewer treatment-related adverse events than in the voriconazole group. This study supports the use of posaconazole as a first-line treatment for the condition. FUNDING: Merck Sharp & Dohme, a subsidiary of Merck & Co, Inc.
Asunto(s)
Antifúngicos/administración & dosificación , Aspergilosis Pulmonar Invasiva/tratamiento farmacológico , Triazoles/administración & dosificación , Voriconazol/administración & dosificación , Administración Intravenosa , Administración Oral , Adolescente , Adulto , Antifúngicos/efectos adversos , Método Doble Ciego , Femenino , Humanos , Aspergilosis Pulmonar Invasiva/mortalidad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Triazoles/efectos adversos , Voriconazol/efectos adversos , Adulto JovenRESUMEN
Posaconazole is approved for use in adults as an intravenous (IV) solution and two different oral formulations (a suspension and an improved bioavailability tablet). Data on the pharmacokinetics (PK), dosing and safety of posaconazole in children are limited. A novel powder for oral suspension (PFS) offers the bioavailability of the tablet formulated for weight-based dosing in children. A non-randomised, open-label, sequential dose-escalation, phase 1b trial evaluated the PK and safety of posaconazole IV and PFS in children aged 2 to 17 years with documented or expected neutropenia (ClinicalTrials.gov, NCT02452034; MSD protocol number, MK-5592-P097). Participants received posaconazole IV 3.5, 4.5 or 6.0 mg/kg/d for ≥10 days, with an option to switch to posaconazole PFS at the identical dose for ≤18 days. The target exposure was a mean within-dose cohort average steady-state plasma concentration (Cavg) of ~1200 ng/mL, with ~90% of participants achieving Cavg between 500 and 2500 ng/mL. Doses of 4.5 and 6.0 mg/kg/d achieved the PK target of ~90% of participants with a Cavg ≥500 ng/mL. PFS resulted in lower posaconazole exposures than IV across age groups at all doses. Posaconazole IV and PFS were well tolerated and had safety profiles similar to those reported for adults. Posaconazole PK following IV and PFS administration was well characterised by the data and enable selection of appropriate paediatric doses. Both formulations were well tolerated without dose-, exposure- or age-related differences in the safety profiles.
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Antifúngicos/farmacocinética , Antifúngicos/uso terapéutico , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Neutropenia/tratamiento farmacológico , Triazoles/farmacocinética , Triazoles/uso terapéutico , Administración Intravenosa , Administración Oral , Adolescente , Antifúngicos/efectos adversos , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Infecciones Fúngicas Invasoras/microbiología , Masculino , Triazoles/efectos adversosRESUMEN
INTRODUCTION: This study characterized the multidose pharmacokinetic (PK) characteristics of posaconazole tablets used as prophylactic antifungal therapy in Chinese patients with acute myelogenous leukemia (AML) at risk for invasive fungal infection (IFI). METHODS: Participants in this open-label, single-arm, phase 1b study received posaconazole 300 mg twice daily on day 1 and then once daily for up to 28 days. In the intensive PK sampling subgroup, posaconazole was administered under fasting conditions on days 1 and 8, and blood samples were regularly collected over 24 h. Trough PK sampling was conducted in all participants on days 1, 2, 3, 8, 14, 21, and 28 without regard for food intake. Population PK characteristics were predicted using PK modeling. Primary endpoints were steady-state average concentration (Cavg) and percentage of participants with steady-state Cavg (predicted and observed) > 500 ng/ml. Treatment safety and efficacy were secondary endpoints. RESULTS: Sixty-five adult Chinese participants were enrolled. On day 8, steady-state arithmetic mean Cavg was 1610 ng/ml (% coefficient of variation [%CV] 42.8%) in the intensive PK subgroup (n = 20). All participants achieved a steady-state Cavg > 500 ng/ml. Predicted Cavg (pCavg) was 1770 ng/ml (%CV 33.7%) in the total population (n = 64); 92.2% of participants had pCavg values ≥ 500 ng/ml (n = 59). The posaconazole tablet safety profile was consistent with that of the oral formulation, and the IFI rate was 3%. CONCLUSION: In Chinese AML patients, the posaconazole 300-mg tablet provided PK data comparable with those of previous studies and was generally well tolerated and efficacious. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02387983.
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Antifúngicos/farmacocinética , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Triazoles/farmacocinética , Administración Oral , Adolescente , Adulto , Anciano , Antifúngicos/efectos adversos , Antifúngicos/uso terapéutico , China , Ayuno , Femenino , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Comprimidos , Triazoles/efectos adversos , Adulto JovenRESUMEN
BACKGROUND: Posaconazole (POS) is a potent triazole antifungal agent approved in adults for treatment and prophylaxis of invasive fungal infections (IFIs). The objectives of this study were to evaluate the pharmacokinetics (PK), safety, and tolerability of POS oral suspension in pediatric subjects with neutropenia. METHODS: This was a prospective, multicenter, sequential dose-escalation study. Enrolled subjects were divided into 3 age groups: AG1, 7 to <18 years; AG2, 2 to <7 years; and AG3, 3 months to <2 years. AG1 and AG2 were divided into 3 dosage cohorts: DC1, 12 mg/kg/day divided twice daily (BID); DC2, 18 mg/kg/day BID; and DC3, 18 mg/kg/day divided thrice daily (TID). AG3 was also divided into DC1 and DC2; however, no subjects were enrolled in DC2. Subjects received 7-28 days of POS oral suspension. PK samples were collected at predefined time points. The POS PK target was predefined as ~90% of subjects with Cavg (AUC /dosing interval) between 500 and 2500 ng/mL, with an anticipated mean steady state Cavg exposure of ~1200 ng/mL. RESULTS: The percentage of subjects meeting the PK target was <90% across all age groups and dosage cohorts (range: 31% to 80%). The percentage of subjects that achieved the Cavg target of 500 to 2500 ng/mL on Day 7 ranged from 31% to 80%, with the lowest proportion in subjects 2 to <7 years receiving 12 mg/kg/day BID (AG2/DC1) and the highest proportion in subjects 7 to <18 years receiving 18 mg/kg/day TID (AG1/DC3). At all three dose levels (12 mg/kg/day BID, 18 mg/kg/day BID and 18 mg/kg/day TID), subjects in AG1 (7 to <18 years old) had higher mean PK exposures at steady state than those in AG2. High variability in exposures was observed in all groups. POS oral suspension was generally well tolerated and most of the reported adverse events were related to the subjects' underlying diseases. CONCLUSION: The POS PK target of 90% of subjects with Cavg between 500 and 2500 ng/mL was not achieved in any of the age groups across the different dosage cohorts. New formulations of the molecule with a greater potential to achieve the established PK target are currently under investigation. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01716234.
Asunto(s)
Antifúngicos/farmacocinética , Área Bajo la Curva , Huésped Inmunocomprometido , Triazoles/farmacocinética , Administración Oral , Adolescente , Factores de Edad , Antifúngicos/administración & dosificación , Antifúngicos/efectos adversos , Antineoplásicos , Niño , Preescolar , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Lactante , Infecciones Fúngicas Invasoras/tratamiento farmacológico , Infecciones Fúngicas Invasoras/inmunología , Infecciones Fúngicas Invasoras/prevención & control , Masculino , Neoplasias/tratamiento farmacológico , Neutropenia/inducido químicamente , Neutropenia/complicaciones , Neutropenia/inmunología , Estudios Prospectivos , Triazoles/administración & dosificación , Triazoles/efectos adversosRESUMEN
A delayed-release solid tablet formulation that releases posaconazole in the small intestine was developed to maximize systemic absorption. This study aimed to characterize the pharmacokinetics of the posaconazole solid tablet formulation in adult subjects and to investigate the potential impact of demographic and clinical factors on posaconazole exposure through a population pharmacokinetic approach. Nonlinear mixed-effects modeling was performed using data from several studies conducted in healthy volunteers and patients. The influence of demographic and clinical factors on pharmacokinetic parameters was evaluated using a stepwise forward inclusion/backward exclusion procedure. The final pharmacokinetic model was used to simulate posaconazole exposure in patients at high risk for invasive fungal diseases treated with the proposed posaconazole dose of 300 mg twice daily on day 1, followed by 300 mg daily for 27 days. A one-compartment pharmacokinetic model with sequential zero-order and first-order absorption and a first-order disposition from the central compartment adequately described the pharmacokinetic profile of the posaconazole solid tablet formulation. Significant covariates included disease state (acute myeloid leukemia/myelodysplasia versus allogeneic hematopoietic stem cell transplantation), body weight, and formulation on bioavailability; food status on first-order absorption rate; and dosing regimen (a single dose versus multiple doses) on clearance. Except for body weight, the impact of these covariates on posaconazole exposure was considered clinically irrelevant. This population pharmacokinetic analysis confirmed that the proposed dose of the posaconazole solid tablet formulation provides adequate target therapeutic exposure (>0.5 mg/liter) to a broad range of patients at high risk for invasive fungal disease.
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Antifúngicos/administración & dosificación , Antifúngicos/farmacocinética , Comprimidos/administración & dosificación , Comprimidos/farmacocinética , Triazoles/administración & dosificación , Triazoles/farmacocinética , Administración Oral , Adulto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVES: A two-part (Phase 1B/3), sequential, open-label, multicentre study evaluated the pharmacokinetics (PK) and safety of intravenous (iv) posaconazole given as antifungal prophylaxis to neutropenic patients with AML or myelodysplastic syndrome (MDS) or to recipients at risk of invasive fungal disease (IFD) after allogeneic HSCT. METHODS: Patients (N = 237) received 300 mg of posaconazole iv twice daily on day 1, followed by 300 mg of posaconazole iv once daily for 4-28 days. After at least 5 days, patients were randomly assigned to receive posaconazole oral suspension, 400 mg twice daily or 200 mg three times daily, to complete a 28 day treatment course. Primary PK parameters were steady-state average concentration over the dosing interval (Cavg) and posaconazole trough levels (Cmin). RESULTS: Mean posaconazole Cmin was 1320 ng/mL (day 6) and 1297 ng/mL (day 8); steady-state Cmin was 1090 ng/mL (day 10). Mean steady-state posaconazole Cavg was 1500 ng/mL (day 10 or 14) and was similar in HSCT recipients (1560 ng/mL) and AML/MDS patients (1470 ng/mL). The most commonly reported treatment-related adverse events were diarrhoea (8%), nausea (5%) and rash (5%). IFD was reported in 3/237 patients (1%; 2 proven, 1 probable). CONCLUSIONS: Intravenous posaconazole at 300 mg was well tolerated, resulted in adequate steady-state systemic exposure and was associated with a low incidence of IFD in this population at high risk. TRIAL REGISTRY AND NUMBER: ClinicalTrials.gov, NCT01075984.
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Antifúngicos/efectos adversos , Antifúngicos/farmacocinética , Quimioprevención/efectos adversos , Quimioprevención/métodos , Infecciones Fúngicas Invasoras/prevención & control , Triazoles/efectos adversos , Triazoles/farmacocinética , Administración Intravenosa , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antifúngicos/administración & dosificación , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Humanos , Huésped Inmunocomprometido , Leucemia Mieloide Aguda/complicaciones , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/complicaciones , Triazoles/administración & dosificación , Adulto JovenRESUMEN
BACKGROUND: Benznidazole is recommended for treatment of Chagas infection. Effects of combination therapy with benznidazole and posaconazole have not been tested in Trypanosoma cruzi carriers. OBJECTIVES: The purpose of this study was to determine whether posaconazole alone or combined with benznidazole were superior to benznidazole monotherapy in eliminating T. cruzi parasites measured by real time polymerase chain reaction (RT-PCR) in asymptomatic Chagas carriers. METHODS: A prospective, multicenter randomized placebo-controlled study was conducted in 120 subjects from Latin America and Spain who were randomized to 4 groups: posaconazole 400 mg twice a day (b.i.d.); benznidazole 200 mg + placebo b.i.d.; benznidazole 200 mg b.i.d. + posaconazole 400 mg b.i.d.; or placebo 10 mg b.i.d. T. cruzi deoxyribonucleic acid was detected by RT-PCR at 30, 60, 90, 120, 150, 180, and 360 days. The primary efficacy outcome is the proportion of subjects with persistent negative RT-PCR by day 180; the secondary outcome was negative RT-PCR at 360 days. RESULTS: Only 13.3% of those receiving posaconazole and 10% receiving placebo achieved the primary outcome, compared with 80% receiving benznidazole + posaconazole and 86.7% receiving benznidazole monotherapy (p < 0.0001 vs. posaconazole/placebo). Posaconazole monotherapy or posaconazole combined with benznidazole achieved high RT-PCR conversion rates during treatment (30 days; 93.3% and 88.9% and 60 days; 90%, and 92.3%) that were similar to benznidazole (89.7% and 89.3%); all were superior to placebo or posaconazole (10% and 16.7%, p < 0.0001). This was not observed at 360 days; benznidazole + posaconazole and benznidazole monotherapy (both 96%) versus placebo (17%) and posaconazole (16%, p < 0.0001). Serious adverse events were rare (6 patients) and were observed in the benznidazole-treated patients. Permanent discontinuation was reported in 19 patients (31.7%) receiving either benznidazole monotherapy or combined with posaconazole. CONCLUSIONS: Posaconazole demonstrated trypanostatic activity during treatment, but it is ineffective long-term in asymptomatic T. cruzi carriers. Benznidazole monotherapy is superior to posaconazole, with high RT-PCR conversion rates sustained at 1 year. Side effects lead to therapy discontinuation in 32%. No advantages were observed with combined therapy versus benznidazole monotherapy. (A Study of the Use of Oral Posaconazole [POS] in the Treatment of Asymptomatic Chronic Chagas Disease [P05267] [STOP CHAGAS]: NCT01377480).
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Enfermedad de Chagas/tratamiento farmacológico , Nitroimidazoles/uso terapéutico , Triazoles/uso terapéutico , Tripanocidas/uso terapéutico , Trypanosoma cruzi , Administración Oral , Adulto , Enfermedad Crónica , Quimioterapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Método Simple CiegoRESUMEN
Chagas disease is caused by the parasitic infection of Trypanosoma cruzi (T. cruzi). The STOP CHAGAS clinical trial was initiated in 2011 to evaluate posaconazole in treating Chagas disease, with treatment success defined as negative qualitative PCR results of detecting the parasites in blood specimens collected post-treatment. PAXgene Blood DNA tubes were utilized as a simple procedure to collect and process blood specimens. However, the PAXgene blood specimens challenged published T. cruzi PCR methods, resulting in poor sensitivity and reproducibility. To accurately evaluate the treatment efficacy of the clinical study, we developed and validated a robust PCR assay for detecting low level T. cruzi in PAXgene blood specimens. The assay combines a new DNA extraction method with a custom designed qPCR assay, resulting in limit of detection of 0.005 and 0.01 fg/µl for K98 and CL Brener, two representative strains of two of T. cruzi's discrete typing units. Reliable qPCR standard curves were established for both strains to measure parasite loads, with amplification efficiency ≥ 90% and the lower limit of linearity ≥ 0.05 fg/µl. The assay successfully analyzed the samples collected from the STOP CHAGAS study and may prove useful for future global clinical trials evaluating new therapies for asymptomatic chronic Chagas disease.
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Sangre/parasitología , Enfermedad de Chagas/parasitología , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Trypanosoma cruzi/aislamiento & purificación , Enfermedad de Chagas/sangre , Enfermedad de Chagas/diagnóstico , ADN Protozoario/sangre , Humanos , Sensibilidad y Especificidad , Trypanosoma cruzi/clasificación , Trypanosoma cruzi/genéticaRESUMEN
BACKGROUND: Antifungal prophylaxis with a new oral tablet formulation of posaconazole may be beneficial to patients at high risk for invasive fungal disease. A two-part (Phase 1B/3) study evaluated posaconazole tablet pharmacokinetics (PK) and safety. METHODS: Patients with neutropenia following chemotherapy for haematological malignancy or recipients of allogeneic HSCT receiving prophylaxis or treatment for graft-versus-host disease received 300 mg posaconazole (as tablets) once daily (twice daily on day 1) for up to 28 days without regard to food intake. Weekly trough PK sampling was performed during therapy, and a subset of patients had sampling on days 1 and 8. Cmin-evaluable subjects received ≥6 days of dosing, and were compliant with specified sampling timepoints. Steady-state PK parameters, safety, clinical failure and survival to day 65 were assessed. ClinicalTrials.gov, NCT01777763; EU Clinical Trials Register, EUDRA-CT 2008-006684-36. RESULTS: Two hundred and ten patients received 300 mg posaconazole (as tablets) once daily. Among Cmin-evaluable subjects (nâ=â186), steady-state mean Cmin was 1720 ng/mL (rangeâ=â210-9140). Steady-state Cmin was ≥700 ng/mL in 90% of subjects with 5% (10 of 186) <500 ng/mL and 5% (10 of 186) 500-700 ng/mL. Six (3%) patients had steady-state Cmin ≥3750 ng/mL. One patient (<1%) had an invasive fungal infection. The most common treatment-related adverse events were nausea (11%) and diarrhoea (8%). There was no increase in adverse event frequency with higher posaconazole exposure. CONCLUSIONS: In patients at high risk for invasive fungal disease, 300 mg posaconazole (as tablets) once daily was well tolerated and demonstrated a safety profile similar to that reported for posaconazole oral suspension: most patients (99%) achieved steady-state pCavg exposures >500 ng/mL and only one patient (<1%) had a pCavg <500 ng/mL.
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Antifúngicos/administración & dosificación , Antifúngicos/farmacocinética , Quimioprevención/métodos , Fungemia/prevención & control , Comprimidos/administración & dosificación , Triazoles/administración & dosificación , Triazoles/farmacocinética , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antifúngicos/efectos adversos , Quimioprevención/efectos adversos , Femenino , Neoplasias Hematológicas/complicaciones , Humanos , Huésped Inmunocomprometido , Masculino , Persona de Mediana Edad , Plasma/química , Análisis de Supervivencia , Comprimidos/efectos adversos , Triazoles/efectos adversos , Adulto JovenRESUMEN
Posaconazole in oral suspension must be taken multiple times a day with food (preferably a high-fat meal) to ensure adequate exposure among patients. We evaluated the effect of food on the bioavailability of a new delayed-release tablet formulation of posaconazole at the proposed clinical dose of 300 mg once daily in a randomized, open-label, single-dose, two-period crossover study with 18 healthy volunteers. When a single 300-mg dose of posaconazole in tablet form (3 tablets × 100 mg) was administered with a high-fat meal, the posaconazole area under the concentration-time curve from 0 to 72 h (AUC0-72) and maximum concentration in plasma (Cmax) increased 51% and 16%, respectively, compared to those after administration in the fasted state. The median time to Cmax (Tmax) shifted from 5 h in the fasted state to 6 h under fed conditions. No serious adverse events were reported, and no subject discontinued the study due to an adverse event. Six of the 18 subjects reported at least one clinical adverse event; all of these events were mild and short lasting. The results of this study demonstrate that a high-fat meal only modestly increases the mean posaconazole exposure (AUC), â¼1.5-fold, after administration of posaconazole tablets, in contrast to the 4-fold increase in AUC observed previously for a posaconazole oral suspension given with a high-fat meal.
Asunto(s)
Antifúngicos/farmacocinética , Comprimidos/farmacocinética , Triazoles/farmacocinética , Administración Oral , Adolescente , Adulto , Anciano , Antifúngicos/administración & dosificación , Antifúngicos/sangre , Estudios Cruzados , Femenino , Humanos , Masculino , Persona de Mediana Edad , Comprimidos/administración & dosificación , Triazoles/administración & dosificación , Triazoles/sangre , Adulto JovenRESUMEN
This study evaluated the safety, tolerability, and pharmacokinetics of a posaconazole i.v. (intravenous) solution. This was a single-center, 2-part, randomized, rising single- and multiple-dose study in healthy adults. In part 1, subjects received 0 (vehicle), 50, 100, 200, 250, or 300 mg posaconazole in a single dose i.v. by 30-min peripheral infusion (6 cohorts of 12 subjects each [9 active and 3 placebo], making a total of 72 subjects). Blood samples were collected until 168 h postdose. In part 2, subjects were to receive 2 peripheral infusions at a 12-h interval on day 1 followed by once-daily infusion for 9 days. However, part 2 was terminated early because of high rates of infusion site reactions with multiple dosing at the same infusion site. The pharmacokinetics results for part 1 (n=45 subjects) showed that the mean posaconazole exposure (area under the concentration-time curve from time zero to infinity [AUC0-∞]) ranged from 4,890 to 46,400 ng · h/ml (range of coefficient of variation values, 26 to 50). The dose-proportionality slope estimate (90% confidence interval) for AUC0-∞ was 1.30 (1.19 to 1.41), indicating a greater-than-dose-proportional increase. The data for safety in part 1 show that 29/72 subjects had ≥1 adverse event. Infusion site reactions were reported in 2/9 vehicle subjects, 0/18 placebo subjects, and 7/45 i.v. posaconazole subjects. The data for safety in part 2 show that infusion site reactions were reported in 1/4 (25%) placebo subjects, 3/9 (33%) vehicle control subjects, and 4/5 (80%) i.v. posaconazole (100 mg) subjects (3 posaconazole recipients subsequently developed thrombophlebitis and were discontinued from treatment). In conclusion, the posaconazole i.v. solution showed a greater-than-dose-proportional increase in exposure, primarily at doses below 200 mg. When administered peripherally at the same infusion site, multiple dosing of i.v. posaconazole led to unacceptably high rates of infusion site reactions. Intravenous posaconazole was otherwise well tolerated. Single doses of i.v. posaconazole were tolerated when given through a peripheral vein over 30 min.