Levofloxacin versus placebo for the prevention of tuberculosis disease in child contacts of multidrug-resistant tuberculosis: study protocol for a phase III cluster randomised controlled trial (TB-CHAMP).

BACKGROUND: Multidrug-resistant (MDR) tuberculosis (TB) presents a challenge for global TB control. Treating individuals with MDR-TB infection to prevent progression to disease could be an effective public health strategy. Young children are at high risk of developing TB disease following infection and are commonly infected by an adult in their household. Identifying young children with household exposure to MDR-TB and providing them with MDR-TB preventive therapy could reduce the risk of disease progression. To date, no trials of MDR-TB preventive therapy have been completed and World Health Organization guidelines suggest close observation with no active treatment. METHODS: The tuberculosis child multidrug-resistant preventive therapy (TB-CHAMP) trial is a phase III cluster randomised placebo-controlled trial to assess the efficacy of levofloxacin in young child contacts of MDR-TB cases. The trial is taking place at three sites in South Africa where adults with MDR-TB are identified. If a child aged < 5 years lives in their household, we assess the adult index case, screen all household members for TB disease and evaluate any child aged < 5 years for trial eligibility. Eligible children are randomised by household to receive daily levofloxacin (15-20 mg/kg) or matching placebo for six months. Children are closely monitored for disease development, drug tolerability and adverse events. The primary endpoint is incident TB disease or TB death by one year after recruitment. We will enrol 1556 children from approximately 778 households with an average of two eligible children per household. Recruitment will run for 18-24 months with all children followed for 18 months after treatment. Qualitative and health economic evaluations are embedded in the trial. DISCUSSION: If the TB-CHAMP trial demonstrates that levofloxacin is effective in preventing TB disease in young children who have been exposed to MDR-TB and that it is safe, well tolerated, acceptable and cost-effective, we would expect that that this intervention would rapidly transfer into policy. TRIAL REGISTRATION: ISRCTN Registry, ISRCTN92634082 . Registered on 31 March 2016.

Challenges of using new and repurposed drugs for the treatment of multidrug-resistant tuberculosis in children.

INTRODUCTION: New and repurposed antituberculosis drugs are urgently needed to more safely and effectively treat multidrug-resistant (MDR) tuberculosis (TB) in children. Multiple challenges limit timely access to new MDR-TB treatments in children. Areas covered: Diagnosis of MDR-TB in children remains a barrier, with few children with MDR-TB diagnosed and treated. Other barriers to timely access to new and repurposed drugs are discussed, and include delayed initiation of paediatric trials, limited funding for paediatric drug development, fragmented regulatory systems and operational challenges. The status of access to current repurposed and novel drugs is presented. Expert commentary: More timely initiation of paediatric trials is needed and paediatric work should happen and be funded in parallel with each phase of adult trials. Better quality data, increased regulator resources and expertise, harmonization of regulatory requirements across borders/organisations and registration fee waivers would improve registration timelines. Improved diagnosis, recording and reporting will establish better demand. Improved systems for procurement and supply chain management would reduce in-country operational barriers to getting medications to children. The challenges must be addressed to ensure timely and equitable access to new drugs and regimens that are urgently needed for effective, safe and shorter treatment of children with MDR-TB.

The epidemiology, pathogenesis, transmission, diagnosis, and management of multidrug-resistant, extensively drug-resistant, and incurable tuberculosis.

Global tuberculosis incidence has declined marginally over the past decade, and tuberculosis remains out of control in several parts of the world including Africa and Asia. Although tuberculosis control has been effective in some regions of the world, these gains are threatened by the increasing burden of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis. XDR tuberculosis has evolved in several tuberculosis-endemic countries to drug-incurable or programmatically incurable tuberculosis (totally drug-resistant tuberculosis). This poses several challenges similar to those encountered in the pre-chemotherapy era, including the inability to cure tuberculosis, high mortality, and the need for alternative methods to prevent disease transmission. This phenomenon mirrors the worldwide increase in antimicrobial resistance and the emergence of other MDR pathogens, such as malaria, HIV, and Gram-negative bacteria. MDR and XDR tuberculosis are associated with high morbidity and substantial mortality, are a threat to health-care workers, prohibitively expensive to treat, and are therefore a serious public health problem. In this Commission, we examine several aspects of drug-resistant tuberculosis. The traditional view that acquired resistance to antituberculous drugs is driven by poor compliance and programmatic failure is now being questioned, and several lines of evidence suggest that alternative mechanisms-including pharmacokinetic variability, induction of efflux pumps that transport the drug out of cells, and suboptimal drug penetration into tuberculosis lesions-are likely crucial to the pathogenesis of drug-resistant tuberculosis. These factors have implications for the design of new interventions, drug delivery and dosing mechanisms, and public health policy. We discuss epidemiology and transmission dynamics, including new insights into the fundamental biology of transmission, and we review the utility of newer diagnostic tools, including molecular tests and next-generation whole-genome sequencing, and their potential for clinical effectiveness. Relevant research priorities are highlighted, including optimal medical and surgical management, the role of newer and repurposed drugs (including bedaquiline, delamanid, and linezolid), pharmacokinetic and pharmacodynamic considerations, preventive strategies (such as prophylaxis in MDR and XDR contacts), palliative and patient-orientated care aspects, and medicolegal and ethical issues.

Assessing the impact of multidrug-resistant tuberculosis in children: an exploratory qualitative study.

BACKGROUND: While the prevalence of multidrug-resistant (MDR) tuberculosis (TB) is high among children in the Western Cape of South Africa, the psychosocial implications of treatment for children with MDR-TB remain poorly understood. We sought to explore how MDR-TB and its treatment impact children on an individual, familial, and social level. METHODS: Semi-structured interviews were conducted with 20 children and caregivers purposively sampled from a prospective clinical cohort of children. The sample was stratified by age at the start of treatment (children >10 years, and 5-10 years). Caregiver proxy interviews were conducted with younger children, supplemented with child interviews; older children were interviewed directly, supplemented with caregiver proxy interviews. Data were analysed using grounded theory. RESULTS: Findings revealed pill volume and adverse effects produced significant physical, psychological and academic disturbances in children. Adverse effects related to the medication were important obstacles to treatment adherence. While there appear to be no long-lasting effects in younger children, a few older children showed evidence of persisting internalised stigma. Caregivers suffered important treatment-related financial and psychological costs. Community support, notably through the continued involvement of children in strong social networks, promoted resilience among children and their families. CONCLUSIONS: We found that the current treatment regimen for childhood MDR-TB has significant psychological, academic, and financial impacts on children and their families. There is a need for psychosocial support of children and caregivers to mitigate the negative effects of community stigma, and to manage the stressors associated with chronic illness.

Multidrug- and extensively drug-resistant tuberculosis in Africa and South America: epidemiology, diagnosis and management in adults and children.

Available data show that Africa, together with the Americas and western and central Europe, reported the lowest prevalence of multidrug-resistant tuberculosis (MDR-TB). However, sub-Saharan Africa has a high TB incidence and the highest human immunodeficiency virus (HIV) prevalence in the world, and because of the high number of TB cases, Africa still presents 14% of the global burden of new MDR-TB cases. Until recently, Africa and South America were deprived of second-line antituberculosis drugs, preventing the development of extensively drug-resistant TB (XDR-TB). Current efforts, introducing improved laboratory infrastructure and second-line TB treatment in resource-limited countries, need to be carried out with care to minimize the development of MDR/XDR-TB in these countries. Recent diagnostic developments now need evaluation and implementation in resource-limited areas, and delays in diagnosis also need to be addressed. Outcomes for MDR/XDR-TB have improved, but prevention of MDR/XDR-TB by early diagnosis and treatment, improvement of adherence, and proper infection control remains the mainstay for the future.

Effect of isoniazid prophylaxis on mortality and incidence of tuberculosis in children with HIV: randomised controlled trial.

OBJECTIVES: To investigate the impact of isoniazid prophylaxis on mortality and incidence of tuberculosis in children with HIV. DESIGN: Two centre prospective double blind placebo controlled trial. PARTICIPANTS: Children aged > or =8 weeks with HIV. INTERVENTIONS: Isoniazid or placebo given with co-trimoxazole either daily or three times a week. SETTING: Two tertiary healthcare centres in South Africa. MAIN OUTCOME MEASURES: Mortality, incidence of tuberculosis, and adverse events. RESULTS: Data on 263 children (median age 24.7 months) were available when the data safety monitoring board recommended discontinuing the placebo arm; 132 (50%) were taking isoniazid. Median follow-up was 5.7 (interquartile range 2.0-9.7) months. Mortality was lower in the isoniazid group than in the placebo group (11 (8%) v 21 (16%), hazard ratio 0.46, 95% confidence interval 0.22 to 0.95, P=0.015) by intention to treat analysis. The benefit applied across Centers for Disease Control clinical categories and in all ages. The reduction in mortality was similar in children on three times a week or daily isoniazid. The incidence of tuberculosis was lower in the isoniazid group (5 cases, 3.8%) than in the placebo group (13 cases, 9.9%) (hazard ratio 0.28, 0.10 to 0.78, P=0.005). All cases of tuberculosis confirmed by culture were in children in the placebo group. CONCLUSIONS: Prophylaxis with isoniazid has an early survival benefit and reduces incidence of tuberculosis in children with HIV. Prophylaxis may offer an effective public health intervention to reduce mortality in such children in settings with a high prevalence of tuberculosis. TRIAL REGISTRATION: Clinical Trials NCT00330304.

Radiographic signs and symptoms in children treated for tuberculosis: possible implications for symptom-based screening in resource-limited settings.

BACKGROUND: The World Health Organization advises active tracing of children younger than 5 years old in household contact with a sputum smear-positive tuberculosis index case. This study compared radiographic disease manifestations in 2 groups of children treated for tuberculosis in an endemic setting: those who presented with suspicious symptoms; and those actively traced as household contacts of an adult index case. METHODS: We conducted a prospective descriptive study from February 2003 through October 2004 at 5 primary health care clinics in Cape Town South Africa, including all children (younger than 5 years old) treated for tuberculosis (TB). RESULTS: A total of 326 children (younger than 5 years old) received antituberculosis treatment; 190 (58.3%) presented with suspicious symptoms, and 136 (41.7%) were actively traced contacts. Children were categorized as; "not TB" 71 (22%), intrathoracic tuberculosis 230 (70%) and extrathoracic tuberculosis 25 (8%). Significantly more actively traced contacts were categorized as "not TB" (odds ratio, 7.4; 95% confidence interval, 3.8-14.3), or demonstrated elements of the primary complex only on the chest radiograph (odds ratio, 26.2; 95% confidence interval, 8.6-89.2), compared with children who presented with suspicious symptoms. Of all children diagnosed with intrathoracic tuberculosis, 20 of 230 (9%) reported no symptoms, all of whom demonstrated elements of the primary complex only. CONCLUSIONS: The majority of actively traced contacts had minimal disease. Symptom-based screening would have identified all but 9% of children diagnosed with intrathoracic tuberculosis, all of whom demonstrated elements of the primary complex only. Further investigation is required to establish whether symptom-based screening can be justified to improve access to preventive chemotherapy in resource-limited endemic settings.