Onno W. Akkerman

Effectiveness and safety of meropenem/ clavulanate-containing regimens in the treatment of MDR- and XDR-TB

No large study has ever evaluated the efficacy, safety and tolerability of meropenem/clavulanate to treat multidrug- and extensively drug-resistant tuberculosis (MDR- and XDR-TB). The aim of this observational study was to evaluate the therapeutic contribution, effectiveness, safety and tolerability profile of meropenem/clavulanate added to a background regimen when treating MDR- and XDR-TB cases. Patients treated with a meropenem/clavulanate-containing regimen (n=96) showed a greater drug resistance profile than those exposed to a meropenem/clavulanate-sparing regimen (n=168): in the former group XDR-TB was more frequent (49% versus 6.0%, p<0.0001) and the median (interquartile range (IQR)) number of antibiotic resistances was higher (8 (6–9) versus 5 (4–6)). Patients were treated with a meropenem/clavulanate-containing regimen for a median (IQR) of 85 (49–156) days. No statistically significant differences were observed in the overall MDR-TB cohort and in the subgroups with and without the XDR-TB patients; in particular, sputum smear and culture conversion rates were similar in XDR-TB patients exposed to meropenem/clavulanate-containing regimens (88.0% versus 100.0%, p=1.00 and 88.0% versus 100.0%, p=1.00, respectively). Only six cases reported adverse events attributable to meropenem/clavulanate (four of them then restarting treatment). The nondifferent outcomes and bacteriological conversion rate observed in cases who were more severe than controls might imply that meropenem/clavulanate could be active in treating MDR- and XDR-TB cases. Meropenem/clavulanate is effective and safe to treat MDR- and XDR-TB in comparison with controls http://ow.ly/XG75j

Microevolution of Mycobacterium tuberculosis in a Tuberculosis Patient

ABSTRACT Five Mycobacterium tuberculosis isolates were obtained from three body sites from a Dutch patient. The isolates displayed a single genotype by 24-locus MIRU-VNTR typing (except for a single locus not amplified from one isolate) but were differentiated by small variations in IS6110 fingerprints, spoligotypes, 6 hypervariable MIRU-VNTR loci, and/or DiversiLab profiles, revealing patterns of microevolution in a clonal infection.

Effectiveness and safety of bedaquiline-containing regimens in the treatment of MDR- and XDR-TB: A multicentre study

Large studies on bedaquiline used to treat multidrug-resistant (MDR-) and extensively drug-resistant tuberculosis (XDR-TB) are lacking. This study aimed to evaluate the safety and effectiveness of bedaquiline-containing regimens in a large, retrospective, observational study conducted in 25 centres and 15 countries in five continents. 428 culture-confirmed MDR-TB cases were analysed (61.5% male; 22.1% HIV-positive, 45.6% XDR-TB). MDR-TB cases were admitted to hospital for a median (interquartile range (IQR)) 179 (92–280) days and exposed to bedaquiline for 168 (86–180) days. Treatment regimens included, among others, linezolid, moxifloxacin, clofazimine and carbapenems (82.0%, 58.4%, 52.6% and 15.3% of cases, respectively). Sputum smear and culture conversion rates in MDR-TB cases were 63.6% and 30.1%, respectively at 30 days, 81.1% and 56.7%, respectively at 60 days; 85.5% and 80.5%, respectively at 90 days and 88.7% and 91.2%, respectively at the end of treatment. The median (IQR) time to smear and culture conversion was 34 (30–60) days and 60 (33–90) days. Out of 247 culture-confirmed MDR-TB cases completing treatment, 71.3% achieved success (62.4% cured; 8.9% completed treatment), 13.4% died, 7.3% defaulted and 7.7% failed. Bedaquiline was interrupted due to adverse events in 5.8% of cases. A single case died, having electrocardiographic abnormalities that were probably non-bedaquiline related. Bedaquiline-containing regimens achieved high conversion and success rates under different nonexperimental conditions. Bedaquiline is safe and effective in treating MDR- and XDR-TB patients http://ow.ly/6MWK30adHkw

Comparison of effectiveness and safety of imipenem/clavulanate- versus meropenem/clavulanate-containing regimens in the treatment of MDR- and XDR-TB

No large study to date has ever evaluated the effectiveness, safety and tolerability of imipenem/clavulanate versus meropenem/clavulanate to treat multidrug- and extensively drug-resistant tuberculosis (MDR- and XDR-TB). The aim of this observational study was to compare the therapeutic contribution of imipenem/clavulanate versus meropenem/clavulanate added to background regimens to treat MDR- and XDR-TB cases. 84 patients treated with imipenem/clavulanate-containing regimens showed a similar median number of antibiotic resistances (8 versus 8) but more fluoroquinolone resistance (79.0% versus 48.9%, p<0.0001) and higher XDR-TB prevalence (67.9% versus 49.0%, p=0.01) in comparison with 96 patients exposed to meropenem/clavulanate-containing regimens. Patients were treated with imipenem/clavulanate- and meropenem/clavulanate-containing regimens for a median (interquartile range) of 187 (60–428) versus 85 (49–156) days, respectively. Statistically significant differences were observed on sputum smear and culture conversion rates (79.7% versus 94.8%, p=0.02 and 71.9% versus 94.8%, p<0.0001, respectively) and on success rates (59.7% versus 77.5%, p=0.03). Adverse events to imipenem/clavulanate and meropenem/clavulanate were reported in 5.4% and 6.5% of cases only. Our study suggests that meropenem/clavulanate is more effective than imipenem/clavulanate in treating MDR/XDR-TB patients. Meropenem/clavulanate is safe and more effective than imipenem/clavulanate in treating MDR and XDR-TB patients http://ow.ly/Z4S2o

Optimization of Standard In-House 24-Locus Variable-Number Tandem-Repeat Typing for Mycobacterium tuberculosis and Its Direct Application to Clinical Material

ABSTRACT Variable-number tandem-repeat (VNTR) typing with a panel of 24 loci is the current gold standard in the molecular typing of Mycobacterium tuberculosis complex isolates. However, because of technical problems, a part of the loci often cannot be amplified by multiplex PCRs. Therefore, a considerable number of single-locus PCRs have to be performed for the loci with missing results, which impairs the laboratory work flow. Therefore, the original in-house method described by Supply et al. in 2006 was reevaluated. We modified seven primers and the PCR master mixture and obtained a strongly optimized in-house 24-locus VNTR typing method. The percentage of instantly complete 24-locus VNTR patterns detected in the routine flow of typing activities increased to 84.7% from the 72.3% obtained with the typing conducted with the commercially available Genoscreen MIRU-VNTR typing kit. The analytical sensitivity of the optimized in-house method was assessed by serial dilutions of M. tuberculosis in bronchoalveolar lavage fluid. A 1:10 dilution of the different strains tested was the lowest dilution for the detection of a complete 24-locus VNTR pattern. The optimized in-house 24-locus VNTR typing method will reduce the turnaround time of typing significantly and also the financial burden of these activities.

Incorporating therapeutic drug monitoring into the World Health Organization hierarchy of tuberculosis diagnostics

Tuberculosis (TB), once considered as a disease of the past generally afflicting poor people, still claims 1.5 million lives annually [1]. Although 86% of patients with drug susceptible TB are cured with established first-line drugs, treatment is often longer than 6 months due to slow response, compliance problems or adverse drug reactions. In addition, emergence of drug-resistant Mycobacterium tuberculosis strains with an unacceptably low treatment success rate of 50% and TB–HIV co-infection have challenged the goals of global TB control and elimination [1]. Incorporating therapeutic drug monitoring into the WHO hierarchy of tuberculosis diagnostics http://ow.ly/YcRMw

Effectiveness and Safety of Imipenem-Clavulanate Added to an Optimized Background Regimen (OBR) Versus OBR Control Regimens in the Treatment of Multidrug-Resistant and Extensively Drug-Resistant Tuberculosis

Simon Tiberi, Giovanni Sotgiu, Lia D’Ambrosio, Rosella Centis, Marcos Abdo Arbex, Edith Alarcon Arrascue, Jan Willem Alffenaar, Jose A. Caminero, Mina Gaga, Gina Gualano, Alena Skrahina, Ivan Solovic, Giorgia Sulis, Marina Tadolini, Valentina Alarcon Guizado, Saverio De Lorenzo, Aurora Jazmin Roby Arias, Anna Scardigli, Onno W. Akkerman, Alena Aleksa, Janina Artsukevich, Vera Avchinko, Eduardo Henrique Bonini, Felix Antonio Chong Marin, Lorena Collahuazo Lopez, Gerard de Vries, Simone Dore, Heinke Kunst, Alberto Matteelli, Charalampos Moschos, Fabrizio Palmieri, Apostolos Papavasileiou, Marie-Christine Payen, Andrea Piana, Antonio Spanevello, Dante Vargas Vasquez, Pietro Viggiani, Veronica White, Alimuddin Zumla and Giovanni Battista Migliori

Bedaquiline and Delamanid Combination Treatment of 5 Patients with Pulmonary Extensively Drug-Resistant Tuberculosis

We report the experiences of 5 patients taking bedaquiline with delamanid in combination: 1 patient was cured; 3 culture converted, with 2 continuing and 1 changing therapy; and 1 died from respiratory insufficiency. For 2 patients, QT-interval prolongation but no arrhythmias occurred. Use of this therapy is justified for patients with limited options.

The Cyclops for pulmonary delivery of aminoglycosides; A new member of the Twincer™ family

Patients infected with pathogenic bacteria have to be treated with antibiotics. When the infection is in the lungs, as for instance in cystic fibrosis, bronchiectasis and tuberculosis, inhaled antibiotics have certain advantages over systemically administered antibiotics. In this study, it is shown that re-designing the Twincer™ high dose disposable inhaler into a device named Cyclops enables effective dispersion of up to 50mg of pure spray dried tobramycin. This proves that spray dried tobramycin powders in the preferred size range for inhalation can be administered without applying complex particle engineering techniques and/or using excipients. Only some coarse sweeper crystals added separately are desired to minimise the inhaler losses to less than 20% at 4 kPa. The fine particle fractions <5 μm of the aerosol obtained from the Cyclops closely resemble the primary particle size distribution of the spray dried tobramycin powder. Moreover, without any further optimisation the Cyclops performs good with other spray dried aminoglycosides such as kanamycin and amikacin too. Therefore, the results of this study show that with an appropriate inhaler design, adapted to the physico-chemical properties of a particular drug or drug class, excellent dispersion can be achieved for high doses of pure (spray dried) drug.

Pharmacokinetics of ertapenem in patients with multidrug-resistant tuberculosis

Treatment of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) is becoming more challenging because of increased levels of drug resistance against second-line TB drugs. One promising group of antimicrobial drugs is carbapenems. Ertapenem is an attractive carbapenem for the treatment of MDR- and XDR-TB because its relatively long half-life enables once-daily dosing. A retrospective study was performed for all patients with suspected MDR-TB at the Tuberculosis Center Beatrixoord of the University Medical Center Groningen (Haren, the Netherlands) who received ertapenem as part of their treatment regimen between December 1, 2010 and March 1, 2013. Safety and pharmacokinetics were evaluated. 18 patients were treated with 1000 mg ertapenem for a mean (range) of 77 (5–210) days. Sputum smear and culture were converted in all patients. Drug exposure was evaluated in 12 patients. The mean (range) area under the concentration–time curve up to 24 h was 544.9 (309–1130) h·mg·L−1. The mean (range) maximum observed plasma concentration was 127.5 (73.9–277.9) mg·L−1. In general, ertapenem treatment was well tolerated during MDR-TB treatment and showed a favourable pharmacokinetic/pharmacodynamic profile in MDR-TB patients. We conclude that ertapenem is a highly promising drug for the treatment of MDR-TB that warrants further investigation. Pharmacokinetic and safety data show ertapenem to be a promising drug for MDR-TB treatment http://ow.ly/V69DD