Bedaquiline-containing regimens in patients with pulmonary multidrug-resistant tuberculosis in China: focus on the safety.

BACKGROUND: World Health Organization recommends countries introducing new drug and short treatment regimen for drug resistant tuberculosis (DR-TB) should develop and implement a system for active pharmacovigilance that allows for detection, reporting and management of adverse events. The aim of the study is to evaluate the frequency and severity of adverse events (AEs) of bedaquiline-containing regimen in a cohort of Chinese patients with multidrug-resistant (MDR)/extensively drug-resistant (XDR)-TB based on active drug safety monitoring (aDSM) system of New Drug Introduction and Protection Program (NDIP). METHODS: AEs were prospectively collected with demographic, bacteriological, radiological and clinical data from 54 sites throughout China at patient enrollment and during treatment between February, 2018 and December, 2019. This is an interim analysis including patients who are still on treatment and those that have completed treatment. A descriptive analysis was performed on the patients evaluated in the cohort. RESULTS: By December 31, 2019, a total of 1162 patients received bedaquiline-containing anti-TB treatment. Overall, 1563 AEs were reported, 66.9% were classified as minor (Grade 1-2) and 33.1% as serious (Grade 3-5). The median duration of bedaquiline treatment was 167.0 [interquartile range (IQR): 75-169] days. 86 (7.4%) patients received 36-week prolonged treatment with bedaquiline. The incidence of AEs and serious AEs was 47.1% and 7.8%, respectively. The most frequently reported AEs were QT prolongation (24.7%) and hepatotoxicity (16.4%). There were 14 (1.2%) AEs leading to death. Out of patients with available corrected QT interval by Fridericia's formula (QTcF) data, 3.1% (32/1044) experienced a post-baseline QTcF ≥ 500 ms, and 15.7% (132/839) had at least one change of QTcF ≥ 60 ms from baseline. 49 (4.2%) patients had QT prolonged AEs leading to bedaquiline withdrawal. One hundred and ninety patients reported 361 AEs with hepatotoxicity ranking the second with high occurrence. Thirty-four patients reported 43 AEs of hepatic injury referred to bedaquiline, much lower than that referred to protionamide, pyrazinamide and para-aminosalicylic acid individually. CONCLUSIONS: Bedaquiline was generally well-tolerated with few safety concerns in this clinical patient population without any new safety signal identified. The mortality rate was generally low. These data inform significant positive effect to support the WHO recent recommendations for the wide use of bedaquiline.

Interferon-Gamma Release Assay is Not Appropriate for the Diagnosis of Active Tuberculosis in High-Burden Tuberculosis Settings: A Retrospective Multicenter Investigation.

BACKGROUND: Interferon-gamma release assay (IGRA) has been used in latent tuberculosis (TB) infection and TB diagnosis, but the results from different high TB-endemic countries are different. The aim of this study was to investigate the value of IGRA in the diagnosis of active pulmonary TB (PTB) in China. METHODS: We conducted a large-scale retrospective multicenter investigation to further evaluate the role of IGRA in the diagnosis of active PTB in high TB-epidemic populations and the factors affecting the performance of the assay. All patients who underwent valid T-SPOT.TB assays from December 2012 to November 2015 in six large-scale specialized TB hospitals in China and met the study criteria were retrospectively evaluated. Patients were divided into three groups: Group 1, sputum culture-positive PTB patients, confirmed by positive Mycobacterium tuberculosis sputum culture; Group 2, sputum culture-negative PTB patients; and Group 3, non-TB respiratory diseases. The medical records of all patients were collected. Chi-square tests and Fisher's exact test were used to compare categorical data. Multivariable logistic analyses were performed to evaluate the relationship between the results of T-SPOT in TB patients and other factors. RESULTS: A total of 3082 patients for whom complete information was available were included in the investigation, including 905 sputum culture-positive PTB cases, 914 sputum culture-negative PTB cases, and 1263 non-TB respiratory disease cases. The positive rate of T-SPOT.TB was 93.3% in the culture-positive PTB group and 86.1% in the culture-negative PTB group. In the non-PTB group, the positive rate of T-SPOT.TB was 43.6%. The positive rate of T-SPOT.TB in the culture-positive PTB group was significantly higher than that in the culture-negative PTB group (χ2 = 25.118, P < 0.01), which in turn was significantly higher than that in the non-TB group (χ2 = 566.116, P < 0.01). The overall results were as follows: sensitivity, 89.7%; specificity, 56.37%; positive predictive value, 74.75%; negative predictive value, 79.11%; and accuracy, 76.02%. CONCLUSIONS: High false-positive rates of T-SPOT.TB assays in the non-TB group limit the usefulness as a single test to diagnose active TB in China. We highly recommend that IGRAs not be used for the diagnosis of active TB in high-burden TB settings.

Genetic polymorphisms of CCL1 rs2072069 G/A and TLR2 rs3804099 T/C in pulmonary or meningeal tuberculosis patients.

CCL1, one of the members of the CC chemokine family, is an inflammatory mediator that stimulates the migration of human monocytes. CCL1 expression is induced by Mycobacterium tuberculosis and TLR ligands in macrophage. TLR2 plays critical role in host immune response against M. tuberculosis infection by regulating the macrophage activation and cytokine secretion. M. tuberculosis causes different clinical forms of tuberculosis (TB) disease. Single-nucleotide polymorphisms (SNPs) in the CCL1 gene and TLR2 gene may be associated with the development of different clinical forms of TB, depending on the different immune mechanisms. This study was to evaluate the possible association between CCL1 rs2072069 G/A or/and TLR2 rs3804099 T/C (T597C) polymorphisms and pulmonary tuberculosis (PTB) or/and tuberculous meningitis (TBM) in a sample of the Chinese adult population. A case-control study was designed to compare the allele frequency and genotype distribution between control (n=386) and TB (n=341) who had either PTB (n=230) or TBM (n=111). The genotype typing was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. TLR2 variant genotype 597CC was associated with susceptibility to PTB rather than to TBM. In the male PTB subgroup, 597CC genotype was identified in a higher rate, compared with male control subgroup. This study demonstrates that T597C polymorphism of TLR2 is a risk factor for susceptibility to PTB rather than to TBM in a sample of Chinese adult population. Patient gender may affect the outcome of M. tuberculosis infection. TLR2 gene may influence the development of PTB and TBM by different immune mechanisms.