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Rationale: Observational studies suggest that high-dose isoniazid may be efficacious in treating multidrug-resistant tuberculosis. However, its activity against Mycobacterium tuberculosis (M.tb) with katG mutations (which typically confer high-level resistance) is not established. Objectives: To characterize the early bactericidal activity (EBA) of high-dose isoniazid in patients with tuberculosis caused by katG-mutated M.tb. Methods: A5312 was a phase IIA randomized, open-label trial. Participants with tuberculosis caused by katG-mutated M.tb were randomized to receive 15 or 20 mg/kg isoniazid daily for 7 days. Daily sputum samples were collected for quantitative culture. Intensive pharmacokinetic sampling was performed on Day 6. Data were pooled across all A5312 participants for analysis (drug-sensitive, inhA-mutated, and katG-mutated M.tb). EBA was determined using nonlinear mixed-effects modeling. Measurements and Main Results: Of 80 treated participants, 21 had katG-mutated M.tb. Isoniazid pharmacokinetics were best described by a two-compartment model with an effect of NAT2 acetylator phenotype on clearance. Model-derived maximum concentration and area under the concentration-time curve in the 15 and 20 mg/kg groups were 15.0 and 22.1 mg/L and 57.6 and 76.8 mg â h/L, respectively. Isoniazid bacterial kill was described using an effect compartment and a sigmoidal maximum efficacy relationship. Isoniazid potency against katG-mutated M.tb was approximately 10-fold lower than in inhA-mutated M.tb. The highest dose of 20 mg/kg did not demonstrate measurable EBA, except against a subset of slow NAT2 acetylators (who experienced the highest concentrations). There were no grade 3 or higher drug-related adverse events. Conclusions: This study found negligible bactericidal activity of high-dose isoniazid (15-20 mg/kg) in the majority of participants with tuberculosis caused by katG-mutated M.tb. Clinical trial registered with www.clinicaltrials.gov (NCT01936831).
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Antituberculosos , Proteínas Bacterianas , Isoniazida , Mutación , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Isoniazida/farmacocinética , Isoniazida/administración & dosificación , Isoniazida/farmacología , Isoniazida/uso terapéutico , Humanos , Antituberculosos/farmacocinética , Antituberculosos/administración & dosificación , Antituberculosos/farmacología , Antituberculosos/uso terapéutico , Femenino , Masculino , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Adulto , Persona de Mediana Edad , Proteínas Bacterianas/genética , Catalasa/genética , Relación Dosis-Respuesta a Droga , Anciano , Pruebas de Sensibilidad MicrobianaRESUMEN
Rationale: Pretomanid is a new nitroimidazole with proven treatment-shortening efficacy in drug-resistant tuberculosis. Pretomanid-rifamycin-pyrazinamide combinations are potent in mice but have not been tested clinically. Rifampicin, but not rifabutin, reduces pretomanid exposures. Objectives: To evaluate the safety and efficacy of regimens containing pretomanid-rifamycin-pyrazinamide among participants with drug-sensitive pulmonary tuberculosis. Methods: A phase 2, 12-week, open-label randomized trial was conducted of isoniazid and pyrazinamide plus 1) pretomanid and rifampicin (arm 1), 2) pretomanid and rifabutin (arm 2), or 3) rifampicin and ethambutol (standard of care; arm 3). Laboratory values of safety and sputum cultures were collected at Weeks 1, 2, 3, 4, 6, 8, 10, and 12. Time to culture conversion on liquid medium was the primary outcome. Measurements and Main Results: Among 157 participants, 125 (80%) had cavitary disease. Median time to liquid culture negativity in the modified intention-to-treat population (n = 150) was 42 (arm 1), 28 (arm 2), and 56 (arm 3) days (P = 0.01) (adjusted hazard ratio for arm 1 vs. arm 3, 1.41 [95% confidence interval (CI), 0.93-2.12; P = 0.10]; adjusted hazard ratio for arm 2 vs. arm 3, 1.89 [95% CI, 1.24-2.87; P = 0.003]). Eight-week liquid culture conversion was 79%, 89%, and 69%, respectively. Grade ≥3 adverse events occurred in 3 of 56 (5%), 5 of 53 (9%), and 2 of 56 (4%) participants. Six participants were withdrawn because of elevated transaminase concentrations (five in arm 2, one in arm 1). There were three serious adverse events (arm 2) and no deaths. Conclusions: Pretomanid enhanced the microbiologic activity of regimens containing a rifamycin and pyrazinamide. Efficacy and hepatic adverse events appeared highest with the pretomanid and rifabutin-containing regimen. Whether this is due to higher pretomanid concentrations merits exploration. Clinical trial registered with www.clinicaltrials.gov (NCT02256696).
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Nitroimidazoles , Tuberculosis Pulmonar , Animales , Ratones , Antituberculosos/efectos adversos , Pirazinamida/uso terapéutico , Rifampin/uso terapéutico , Quimioterapia Combinada , Isoniazida/uso terapéutico , Nitroimidazoles/efectos adversos , Tuberculosis Pulmonar/tratamiento farmacológico , Tuberculosis Pulmonar/microbiologíaRESUMEN
BACKGROUND: The WHO-endorsed shorter-course regimen for MDR-TB includes high-dose isoniazid. The pharmacokinetics of high-dose isoniazid within MDR-TB regimens has not been well described. OBJECTIVES: To characterize isoniazid pharmacokinetics at 5-15â mg/kg as monotherapy or as part of the MDR-TB treatment regimen. METHODS: We used non-linear mixed-effects modelling to evaluate the combined data from INHindsight, a 7â day early bactericidal activity study with isoniazid monotherapy, and PODRtb, an observational study of patients on MDR-TB treatment including terizidone, pyrazinamide, moxifloxacin, kanamycin, ethionamide and/or isoniazid. RESULTS: A total of 58 and 103 participants from the INHindsight and PODRtb studies, respectively, were included in the analysis. A two-compartment model with hepatic elimination best described the data. N-acetyltransferase 2 (NAT2) genotype caused multi-modal clearance, and saturable first-pass was observed beyond 10â mg/kg dosing. Saturable isoniazid kinetics predicted an increased exposure of approximately 50% beyond linearity at 20â mg/kg dosing. Participants treated with the MDR-TB regimen had a 65.6% lower AUC compared with participants on monotherapy. Ethionamide co-administration was associated with a 29% increase in isoniazid AUC. CONCLUSIONS: Markedly lower isoniazid exposures were observed in participants on combination MDR-TB treatment compared with monotherapy. Isoniazid displays saturable kinetics at doses >10â mg/kg. The safety implications of these phenomena remain unclear.
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Arilamina N-Acetiltransferasa , Mycobacterium tuberculosis , Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis Pulmonar , Antituberculosos/efectos adversos , Arilamina N-Acetiltransferasa/farmacología , Etionamida/farmacología , Etionamida/uso terapéutico , Humanos , Isoniazida/farmacocinética , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Pulmonar/tratamiento farmacológicoRESUMEN
Rationale: There is accumulating evidence that higher-than-standard doses of isoniazid are effective against low-to-intermediate-level isoniazid-resistant strains of Mycobacterium tuberculosis, but the optimal dose remains unknown. Objectives: To characterize the association between isoniazid pharmacokinetics (standard or high dose) and early bactericidal activity against M. tuberculosis (drug sensitive and inhA mutated) and N-acetyltransferase 2 status. Methods: ACTG (AIDS Clinical Trial Group) A5312/INHindsight is a 7-day early bactericidal activity study with isoniazid at a normal dose (5 mg/kg) for patients with drug-sensitive bacteria and 5, 10, and 15 mg/kg doses for patients with inhA mutants. Participants with pulmonary tuberculosis received daily isoniazid monotherapy and collected sputum daily. Colony-forming units (cfu) on solid culture and time to positivity in liquid culture were jointly analyzed using nonlinear mixed-effects modeling. Measurements and Main Results: Fifty-nine adults were included in this analysis. A decline in sputum cfu was described by a one-compartment model, whereas an exponential bacterial growth model was used to interpret time-to-positivity data. The model found that bacterial kill is modulated by isoniazid concentration using an effect compartment and a sigmoidal Emax relationship (a model linking the drug concentration to the observed effect). The model predicted lower potency but similar maximum kill of isoniazid against inhA-mutated compared with drug-sensitive isolates. Based on simulations from the pharmacokinetics-pharmacodynamics model, to achieve a drop in bacterial load comparable to 5 mg/kg against drug-sensitive tuberculosis, 10- and 15-mg/kg doses are necessary against inhA-mutated isolates in slow and intermediate N-acetyltransferase 2 acetylators, respectively. Fast acetylators underperformed even at 15 mg/kg. Conclusions: Dosing of isoniazid based on N-acetyltransferase 2 acetylator status may help patients attain effective exposures against inhA-mutated isolates. Clinical trial registered with www.clinicaltrials.gov (NCT01936831).
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Antituberculosos/administración & dosificación , Isoniazida/administración & dosificación , Esputo/microbiología , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico , Tuberculosis Pulmonar/tratamiento farmacológico , Adulto , Antituberculosos/farmacocinética , Arilamina N-Acetiltransferasa , Proteínas Bacterianas , Recuento de Colonia Microbiana , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Isoniazida/farmacocinética , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Oxidorreductasas , Tuberculosis Resistente a Múltiples Medicamentos/metabolismo , Tuberculosis Resistente a Múltiples Medicamentos/microbiología , Tuberculosis Pulmonar/metabolismo , Tuberculosis Pulmonar/microbiología , Adulto JovenRESUMEN
Shorter, more potent regimens are needed for tuberculosis. The nitroimidazole pretomanid was recently approved for extensively drug-resistant tuberculosis in combination with bedaquiline and linezolid. Pretomanid may also have benefit as a treatment-shortening agent for drug-sensitive tuberculosis. It is unclear how and whether it can be used together with rifamycins, which are key sterilizing first-line drugs. In this analysis, data were pooled from two studies: the Assessing Pretomanid for Tuberculosis (APT) trial, in which patients with drug-sensitive pulmonary TB received pretomanid, isoniazid, and pyrazinamide plus either rifampin or rifabutin versus standard of care under fed conditions, and the AIDS Clinical Trials Group 5306 (A5306) trial, a phase I study in healthy volunteers receiving pretomanid alone or in combination with rifampin under fasting conditions. In our population pharmacokinetic (PK) model, participants taking rifampin had 44.4 and 59.3% reductions in pretomanid AUC (area under the concentration-time curve) compared to those taking rifabutin or pretomanid alone (due to 80 or 146% faster clearance) in the APT and A5306 trials, respectively. Median maximum concentrations (Cmax) in the rifampin and rifabutin arms were 2.14 and 3.35 mg/liter, while median AUC0-24 values were 30.1 and 59.5 mg·h/liter, respectively. Though pretomanid exposure in APT was significantly reduced with rifampin, AUC0-24 values were similar to those associated with effective treatment in registrational trials, likely because APT participants were fed with dosing, enhancing pretomanid relative bioavailability and exposures. Pretomanid concentrations with rifabutin were high but in range with prior observations. While pretomanid exposures with rifampin are unlikely to impair efficacy, our data suggest that pretomanid should be taken with food if prescribed with rifampin. (This study has been registered at ClinicalTrials.gov under identifier NCT02256696.).
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Nitroimidazoles , Rifamicinas , Antituberculosos/uso terapéutico , Humanos , Nitroimidazoles/uso terapéutico , Pirazinamida/uso terapéuticoRESUMEN
New modalities of Pre-exposure Prophylaxis (PrEP) such as long-acting injectable PrEP (LAI-PrEP) promise increased prevention of HIV transmission; however, similar biomedical interventions have not been met with universal adoption by healthcare providers or populations most affected by HIV. This qualitative study explores healthcare provider considerations for the rollout of LAI-PrEP. Eleven key-informant in-depth interviews were conducted with clinicians who prescribe daily oral PrEP. Participants reviewed a currently proposed LAI regimen and were asked to reflect on its implications for their clinical practice. Interviews were transcribed verbatim and thematically coded, with results organized using the Consolidated Framework for Implementation Research (CFIR). All participants expressed interest in prescribing LAI-PrEP and anticipated that at least some patients would be interested. Participants identified characteristics of the intervention, inner intervention setting, and outer intervention setting that will be influential in bringing LAI-PrEP to scale. Clinicians in the South have unique insights into the challenges of and opportunities for successful rollout of future PrEP regimens. Bringing these insights into a CFIR framework highlights the nuances surrounding LAI-PrEP, including structural concerns such as cost barriers and access to in-person healthcare services. It is critical to address these challenges to ensure successful implementation of new PrEP formulations.
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Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Fármacos Anti-VIH/uso terapéutico , Georgia , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Personal de Salud , HumanosRESUMEN
Rationale: High-dose isoniazid is recommended in short-course regimens for multidrug-resistant tuberculosis (TB). The optimal dose of isoniazid and its individual contribution to efficacy against TB strains with inhA or katG mutations are unknown.Objectives: To define the optimal dose of isoniazid for patients with isoniazid-resistant TB mediated by inhA mutations.Methods: AIDS Clinical Trials Group A5312 is a phase 2A, open-label trial in which individuals with smear-positive pulmonary TB with isoniazid resistance mediated by an inhA mutation were randomized to receive isoniazid 5, 10, or 15 mg/kg daily for 7 days (inhA group), and control subjects with drug-sensitive TB received the standard dose (5 mg/kg/d). Overnight sputum cultures were collected daily. The 7-day early bactericidal activity (EBA) of isoniazid was estimated as the average daily change in log10 cfu on solid media (EBAcfu0-7) or as time to positivity (TTP) in liquid media in hours (EBATTP0-7) using nonlinear mixed-effects models.Measurements and Main Results: Fifty-nine participants (88% with cavitary disease, 20% HIV-positive, 16 with isoniazid-sensitive TB, and 43 with isoniazid-monoresistant or multidrug-resistant TB) were enrolled at one site in South Africa. The mean EBAcfu0-7 at doses of 5, 10, and 15 mg/kg in the inhA group was 0.07, 0.17, and 0.22 log10 cfu/ml/d, respectively, and 0.16 log10 cfu/ml/d in control subjects. EBATTP0-7 patterns were similar. There were no drug-related grade ≥3 adverse events.Conclusions: Isoniazid 10-15 mg/kg daily had activity against TB strains with inhA mutations similar to that of 5 mg/kg against drug-sensitive strains. The activity of high-dose isoniazid against strains with katG mutations will be explored next.Clinical trial registered with www.clinicaltrials.gov (NCT01936831).
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PURPOSE OF REVIEW: Despite broad uptake of antiretroviral therapy (ART), tuberculosis (TB) incidence and mortality among people with HIV remain unacceptably high. Short-course regimens for TB, incorporating both novel and established drugs, offer the potential to enhance adherence and completion rates, thereby reducing the global TB burden. This review will outline short-course regimens for TB among patients with HIV. RECENT FINDINGS: After many years without new agents, there is now active testing of many novel drugs to treat TB, both for latent infection and active disease. Though not all studies have included patients with HIV, many have, and there are ongoing trials to address key implementation challenges such as potent drug-drug interactions with ART. The goal of short-course regimens for TB is to enhance treatment completion without compromising efficacy. Particularly among patients with HIV, studying these shortened regimens and integrating them into clinical care are of urgent importance. There are now multiple short-course regimens for latent infection and active disease that are safe and effective among patients with HIV.
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Fármacos Anti-VIH/uso terapéutico , Antituberculosos/uso terapéutico , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Infecciones por VIH/tratamiento farmacológico , Tuberculosis Pulmonar/tratamiento farmacológico , Interacciones Farmacológicas , Humanos , Isoniazida/uso terapéutico , Pirazinamida/uso terapéutico , Rifampin/análogos & derivados , Rifampin/uso terapéuticoAsunto(s)
Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Humanos , Isoniazida , Pirazinamida , RifampinRESUMEN
BACKGROUND: Long-term treatment-related outcomes in patients with extensively drug-resistant (XDR) tuberculosis are unknown. We followed up a cohort of patients to address knowledge gaps. METHODS: Between March, 2008, and August, 2012, we prospectively followed up a cohort of 107 patients from three provinces in South Africa, who had been diagnosed with XDR tuberculosis between August 2002, and February, 2008. Available isolates from 56 patients were genotyped to establish strain type and used for extended susceptibility testing. FINDINGS: All patients were treated empirically as inpatients with a median of eight drugs (IQR six to ten). 44 patients (41%) had HIV. 36 (64%) of 56 isolates were resistant to at least eight drugs, and resistance to an increasing number of drugs was associated with the Beijing genotype (p=0·01). After 24 months of follow-up, 17 patients (16%) had a favourable outcome (ie, treatment cure or completion), 49 (46%) had died, seven (7%) had defaulted (interruption of treatment for at least 2 consecutive months), and 25 (23%) had failed treatment. At 60 months, 12 patients (11%) had a favourable outcome, 78 (73%) had died, four (4%) had defaulted, and 11 (10%) had failed treatment. 45 patients were discharged from hospital, of whom 26 (58%) had achieved sputum culture conversion and 19 (42%) had failed treatment. Median survival of patients who had failed treatment from time of discharge was 19·84 months (IQR 4·16-26·04). Clustering of cases and transmission within families containing a patient who had failed treatment and been discharged were shown with genotypic methods. Net sputum culture conversion occurred in 22 patients (21%) and median time to net culture conversion was 8·7 months (IQR 5·6-26·4). Independent predictors of probability of net culture conversion were no history of multidrug-resistant tuberculosis (p=0·0007) and use of clofazamine (p=0·0069). Independent overall predictors of survival were net culture conversion (p<0·0001) and treatment with clofazamine (p=0·021). Antiretroviral therapy was also a predictor of survival in patients with HIV (p=0·003). INTERPRETATION: In South Africa, long-term outcomes in patients with XDR tuberculosis are poor, irrespective of HIV status. Because appropriate long-stay or palliative care facilities are scarce, substantial numbers of patients with XDR tuberculosis who have failed treatment and have positive sputum cultures are being discharged from hospital and are likely to transmit disease into the wider community. Testing of new combined regimens is needed urgently and policy makers should implement interventions to minimise disease spread by patients who fail treatment. FUNDING: European and Developing Countries Clinical Trials Partnership, South African National Research Foundation (SARChI), and the South African Medical Research Council.
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Antituberculosos/uso terapéutico , Tuberculosis Extensivamente Resistente a Drogas/tratamiento farmacológico , Adulto , Coinfección/complicaciones , Coinfección/mortalidad , Tuberculosis Extensivamente Resistente a Drogas/complicaciones , Tuberculosis Extensivamente Resistente a Drogas/mortalidad , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/mortalidad , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sudáfrica/epidemiología , Esputo/microbiología , Resultado del TratamientoRESUMEN
Mycobacteroides abscessus (Mab, also known as Mycobacterium abscessus) causes opportunistic pulmonary and soft tissue infections that are difficult to cure with existing treatments. Omadacycline, a new tetracycline antibiotic, exhibits potent in vitro and in vivo activity against Mab. As regimens containing multiple antibiotics are required to produce a durable cure for Mab disease, we assessed efficacies of three three-drug combinations in a pre-clinical mouse model of pulmonary Mab disease to identify companion drugs with which omadacycline exhibits the highest efficacy. Additionally, we assessed the susceptibility of Mab recovered from mouse lungs after four weeks of exposure to the three triple-drug regimens. Among the three-drug regimens, omadacycline + imipenem + amikacin produced the largest reduction in Mab burden, whereas omadacycline + imipenem + linezolid exhibited the most effective early bactericidal activity. Omadacycline + linezolid + clofazimine, a regimen that can be administered orally, lacked early bactericidal activity but produced a gradual reduction in the lung Mab burden over time. The robust efficacy exhibited by these three regimens in the mouse model supports their further evaluation in patients with Mab lung disease. As we were unable to isolate drug-resistant Mab mutants at the completion of four weeks of treatment, these triple-drug combinations show promise of producing durable cure and minimizing selection of resistant mutants.
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Infecciones por Mycobacterium no Tuberculosas , Mycobacterium abscessus , Mycobacterium tuberculosis , Humanos , Animales , Ratones , Linezolid/farmacología , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Tetraciclinas/farmacología , Tetraciclinas/uso terapéutico , Imipenem/farmacología , Combinación de Medicamentos , Pruebas de Sensibilidad MicrobianaRESUMEN
Treatment outcomes for Mycobacteroides abscessus (Mab, also known as Mycobacterium abscessus) disease are still unsatisfactory, mainly due to issues with drug toxicity, tolerability, and efficacy. Treating Mab disease is challenging due to its high baseline antibiotic resistance, initial requirement for intravenous therapy, and poor medication tolerance. Omadacycline, a new tetracycline, is active against Mab. Since any new antibiotic effective against Mab is expected to be used in combination with other antibiotics, we evaluated the efficacy of two triple-drug combinations comprising omadacycline, omadacycline + amikacin + imipenem, and omadacycline + clofazimine + linezolid against two contemporary Mab clinical isolates in a mouse model of Mab lung disease. Antibiotic administration was initiated 1-week post-infection and was given daily, with Mab burden in the lungs at treatment completion serving as the endpoint. Omadacycline alone moderately reduced Mab levels and maintained better health in mice compared to untreated ones, which typically suffered from the infection. The omadacycline + clofazimine + linezolid combination showed immediate bactericidal activity and enhanced efficacy over 6 weeks, particularly against the more resistant strain (M9507). However, the clofazimine + linezolid combination lacked early bactericidal activity. When combined with amikacin and imipenem, omadacycline did not improve the regimen's effectiveness over 4 weeks of treatment. Our study showed that omadacycline + clofazimine + linezolid exhibited significant bactericidal activity over an extended treatment duration. However, adding omadacycline to amikacin and imipenem did not improve regimen effectiveness against the evaluated clinical isolates within 4 weeks. Further research in Mab disease patients is needed to determine the most effective omadacycline-containing regimen.IMPORTANCEMycobacteroides abscessus is a common environmental bacterium that causes infections in people with compromised lung function, including those with bronchiectasis, cystic fibrosis, chronic obstructive pulmonary disease, and weakened immune systems, especially among older individuals. Treating M. abscessus disease is challenging due to the limited effectiveness and toxicity of current antibiotics, which often require prolonged use. Omadacycline, a new antibiotic, shows promise against M. abscessus. Using a mouse model that mimics M. abscessus disease in humans, we studied the effectiveness of including omadacycline with recommended antibiotics. Adding omadacycline to clofazimine and linezolid significantly improved treatment outcomes, rapidly clearing the bacteria from the lungs and maintaining effectiveness throughout. This oral combination is convenient for patients. However, adding omadacycline to amikacin and imipenem did not improve treatment effectiveness within 4 weeks. Further study with M. abscessus patients is necessary to optimize omadacycline-based treatment strategies for this disease.
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Amicacina , Antibacterianos , Clofazimina , Modelos Animales de Enfermedad , Quimioterapia Combinada , Imipenem , Linezolid , Infecciones por Mycobacterium no Tuberculosas , Mycobacterium abscessus , Tetraciclinas , Animales , Clofazimina/administración & dosificación , Clofazimina/uso terapéutico , Linezolid/administración & dosificación , Linezolid/uso terapéutico , Ratones , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Amicacina/administración & dosificación , Amicacina/uso terapéutico , Tetraciclinas/administración & dosificación , Tetraciclinas/uso terapéutico , Tetraciclinas/farmacología , Mycobacterium abscessus/efectos de los fármacos , Imipenem/administración & dosificación , Imipenem/uso terapéutico , Imipenem/farmacología , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Femenino , Resultado del Tratamiento , Pruebas de Sensibilidad Microbiana , Enfermedades Pulmonares/tratamiento farmacológico , Enfermedades Pulmonares/microbiología , Administración Oral , Pulmón/microbiologíaRESUMEN
Mycobacteroides abscessus is an opportunistic pathogen in people with structural lung conditions such as bronchiectasis, chronic obstructive pulmonary disease, and cystic fibrosis. Pulmonary M. abscessus infection causes progressive symptomatic and functional decline as well as diminished lung function and is often incurable with existing antibiotics. We investigated the efficacy of a new tetracycline, omadacycline, in combination with existing antibiotics recommended to treat this indication, in a mouse model of M. abscessus lung disease. Amikacin, azithromycin, bedaquiline, biapenem, cefoxitin, clofazimine, imipenem, linezolid, and rifabutin were selected as companions to omadacycline. M. abscessus burden in the lungs of mice over a 4-week treatment duration was considered the endpoint. Omadacycline in combination with linezolid, imipenem, cefoxitin, biapenem, or rifabutin exhibited early bactericidal activity compared to any single drug. Using three M. abscessus isolates, we also determined the in vitro frequency of spontaneous resistance against omadacycline to be between 1.9 × 10-10 and 6.2 × 10-10 and the frequency of persistence against omadacycline to be between 5.3 × 10-6 and 1.3 × 10-5. Based on these findings, the combination of omadacycline and select drugs that are included in the recent treatment guidelines may exhibit improved potency to treat M. abscessus lung disease. IMPORTANCE M. abscessus disease incidence is increasing in the United States. This disease is difficult to cure with existing antibiotics. In this study, we describe the efficacy of a new tetracycline antibiotic, omadacycline, in combination with an existing antibiotic to treat this disease. A mouse model of M. abscessus lung disease was used to assess the efficacies of these experimental treatment regimens. Omadacycline in combination with select existing antibiotics exhibited bactericidal activity during the early phase of treatment.
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Fibrosis Quística , Mycobacterium abscessus , Animales , Ratones , Linezolid , Cefoxitina , Pruebas de Sensibilidad Microbiana , Antibacterianos/uso terapéutico , Tetraciclinas/uso terapéutico , Imipenem , RifabutinaRESUMEN
An elderly man with refractory Mycobacterium abscessus lung disease previously developed anti-phage neutralizing antibodies while receiving intravenous phage therapy. Subsequent phage nebulization resulted in transient weight gain, decreased C-reactive protein, and reduced Mycobacterium burden. Weak sputum neutralization may have limited the outcomes, but phage resistance was not a contributing factor.
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A method for the extraction and quantification of pretomanid in 40⯵L of human plasma, by high performance liquid chromatography with tandem mass spectrometry (LC-MS/MS) detection was developed and validated. Samples were prepared using liquid-liquid extraction and chromatographic separation was achieved on an Agilent Poroshell C18 column using an isocratic elution at a flow rate of 400⯵L/min. Electrospray ionization with mass detection at unit resolution in the multiple reaction monitoring (MRM) mode on an AB Sciex API 3200 mass spectrometer was used. Over the validation period, accuracy, precision, selectivity, sensitivity, recovery and stability were assessed. The calibration range was 10 - 10 000â¯ng/mL. Inter- and intra-day precision, expressed as the coefficient of variation (%CV), was shown to be lower than 9% at all concentrations tested with accuracies between 95.2 and 110 %. The recovery was 72.4 % overall and reproducible at the low, medium and high end of the calibration range. The method was shown to be specific for pretomanid with no significant matrix effects observed. The validated method facilitated the analysis of pretomanid in plasma collected from adults with pulmonary TB as part of a clinical pharmacokinetic study.
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Espectrometría de Masas en Tándem , Tuberculosis Pulmonar , Adulto , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Humanos , Nitroimidazoles , Reproducibilidad de los Resultados , Espectrometría de Masa por Ionización de Electrospray , Tuberculosis Pulmonar/diagnósticoRESUMEN
BACKGROUND: There is currently no single treatment that mitigates all harms caused by severe acute respiratory syndrome coronavirus 2 infection. Tocilizumab, an interleukin-6 antagonist, may have a role as an adjunctive immune-modulating therapy. METHODS: This was an observational retrospective study of hospitalized adult patients with confirmed coronavirus disease 2019 (COVID-19). The intervention group comprised patients who received tocilizumab; the comparator arm was drawn from patients who did not receive tocilizumab. The primary outcome was all-cause mortality censored at 28 days; secondary outcomes were all-cause mortality at discharge, time to clinical improvement, and rates of secondary infections. Marginal structural Cox models via inverse probability treatment weights were applied to estimate the effect of tocilizumab. A time-dependent propensity score-matching method was used to generate a 1:1 match for tocilizumab recipients; infectious diseases experts then manually reviewed these matched charts to identify secondary infections. RESULTS: This analysis included 90 tocilizumab recipients and 1669 controls. Under the marginal structural Cox model, tocilizumab was associated with a 62% reduced hazard of death (adjusted hazard ratio [aHR], 0.38; 95% CI, 0.21 to 0.70) and no change in time to clinical improvement (aHR, 1.13; 95% CI, 0.68 to 1.87). The 1:1 matched data set also showed a lower mortality rate (27.8% vs 34.4%) and reduced hazards of death (aHR, 0.47; 95% CI, 0.25 to 0.88). Elevated inflammatory markers were associated with reduced hazards of death among tocilizumab recipients compared with controls. Secondary infection rates were similar between the 2 groups. CONCLUSIONS: Tocilizumab may provide benefit in a subgroup of patients hospitalized with COVID-19 who have elevated biomarkers of hyperinflammation, without increasing the risk of secondary infection.
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Tuberculosis (TB) continues to affect over 10 million people per year worldwide. Despite advances in diagnosis, smear microscopy insufficiently detects pulmonary disease, with test result reporting taking longer than a day. While urine assays to detect the lipopolysaccharide lipoarabinomannan (LAM), present in mycobacterial cell walls, can provide results within minutes, the currently available assay has low sensitivity and its application is limited to patients with HIV suspected of having TB. In this issue of the JCI, Broger and Nicol et al. investigated 3 rapid urine tests in 372 ambulatory HIV-negative individuals suspected of having TB in South Africa and Peru. FujiLAM emerged as a rapid test to confirm TB diagnosis in the HIV-seronegative population. This study shows that FujiLAM has considerable potential to reshape the TB diagnostics landscape, making diagnosis and treatment in one office visit a reality for TB.
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Infecciones por VIH , Tuberculosis , Infecciones por VIH/diagnóstico , Humanos , Lipopolisacáridos , Pacientes Ambulatorios , Sistemas de Atención de Punto , Pruebas en el Punto de Atención , Sensibilidad y Especificidad , Sudáfrica , Tuberculosis/diagnósticoRESUMEN
Tuberculosis (TB) has now surpassed HIV as the leading infectious cause of death, and treatment success rates are declining. Multidrug-resistant TB, extensively drug-resistant TB, and even totally drug-resistant TB threaten to further destabilize disease control efforts. The second wave in TB drug development, which includes the diarylquinoline, bedaquiline, and the nitroimidazoles delamanid and pretomanid, may offer options for simpler, shorter, and potentially all-oral regimens to treat drug-resistant TB. The "third wave" of TB drug development includes numerous promising compounds, including less toxic versions of older drug classes and candidates with novel mechanisms of action.