Cognitive impairment in tuberculous meningitis

BACKGROUND: Cognitive impairment is reported as a common complication in adult tuberculous meningitis (TBM), yet few studies have systematically assessed the frequency and nature of impairment. Moreover, the impact of impairment on functioning and medication adherence is not described. METHODS: A cognitive test battery (10 measures assessing 7 cognitive domains) was administered to 34 participants with HIV-associated TBM 6 months post-diagnosis. Cognitive performance was compared to a comparator group of 66 people living with HIV (PLWH) without a history of TB. A secondary comparison was made between TBM cases and 26 participants with HIV 6-months post diagnosis of TB outside the central nervous system (CNS). Impact on functioning was evaluated, including through assessment of medication adherence. RESULTS: In TBM, 16/34 (47%) of participants had low performance on cognitive testing. Cognition was impaired across all domains. Global cognitive performance was significantly lower in TBM cases compared to PLWH (mean T-score 41 vs 48, p < 0.001). TBM cases also had lower global cognition compared to those with non-CNS TB (mean global T score 41 vs 46, p = 0.016). Functional outcomes did not significantly correlate with cognitive performance in the sub-group of participants where this was assessed (n = 19). CONCLUSIONS: Low cognitive performance following HIV-associated TBM is common. This effect is independent of, and additional to, effects of HIV and non-CNS TB disease. Further studies are needed to understand longer term outcomes, clarify the association with treatment adherence, a key predictor of outcome in TBM, and develop context-specific tools to identify individuals with cognitive difficulties to improve outcomes in TBM

Plasma pharmacokinetics of high dose oral versus intravenous rifampicin in patients with tuberculous meningitis: a randomized controlled trial

Background Higher doses of intravenous rifampicin may improve outcomes in tuberculous meningitis but is impractical in high burden settings. We hypothesized that plasma rifampicin exposures would be similar between oral 35 mg/kg and intravenous 20 mg/kg, which has been proposed for efficacy trials in tuberculous meningitis. Materials and methods We performed a randomized parallel group pharmacokinetic study nested within a clinical trial of intensified antimicrobial therapy for tuberculous meningitis. HIV-positive participants with tuberculous meningitis were recruited from South African hospitals and randomized to one of three rifampicin dosing groups: standard (oral 10 mg/kg), high dose (oral 35 mg/kg), and intravenous (intravenous 20 mg/kg). Intensive pharmacokinetic sampling was done on day 3. Data were described using non-compartmental analysis and exposures compared by geometric mean ratio (GMR). Results Forty-six participants underwent pharmacokinetic sampling (standard dose, n = 17; high dose oral, n= 15; intravenous, n = 14). Median CD4 count was 130 cells/mm3 (IQR 66 - 253). Rifampicin geometric mean AUC0-24 was 42.9 μg·h/mL (95% CI, 24.5 – 75.0) for standard dose; 295.2 μg·h/mL (95% CI, 189.9 – 458.8) for high dose oral; and 206.5 μg·h/mL (95% CI, 154.6 – 275.8) for intravenous administration. Rifampicin AUC0-24 GMR was 1.44 (90% CI, 0.84 - 2.21) and Cmax GMR was 0.89 (90% CI, 0.63 – 1.23) for high dose oral with respect to intravenous dosing. Conclusions Plasma rifampicin AUC0-24 was higher after an oral 35 mg/kg dose compared with intravenous administration at 20 mg/kg dose over the first few days of TB treatment. Findings support oral rifampicin dosing in future tuberculous meningitis trials

Capacity building in Sub-Saharan Africa as part of the INTENSE-TBM Project during the COVID-19 pandemic

Tuberculous meningitis (TBM) is the most severe and disabling form of tuberculosis (TB), with at least 100,000 cases per year and a mortality rate of up to 50% in individuals co-infected with human immunodeficiency virus type 1 (HIV-1). To evaluate the efficacy and safety of an intensified anti-tubercular regimen and an anti-inflammatory treatment, the INTENSE-TBM project includes a phase III randomised clinical trial (TBM-RCT) in four countries in sub-Saharan Africa (SSA). Within this framework, we designed a comprehensive capacity-building work package ensuring all centres had, or would acquire, the ability to conduct the TBM-RCT and developing a network of skilled researchers, clinical centres and microbiology laboratories. Here, we describe these activities, identify strengths/challenges and share tools adaptable to other projects, particularly in low- and lower-middle income countries with heterogeneous settings and during the coronavirus disease 2019 (COVID-19) pandemic. Despite major challenges, TBM-RCT initiation was achieved in all sites, promoting enhanced local healthcare systems and encouraging further clinical research in SSA. In terms of certified trainings, the achievement levels were 95% (124/131) for good clinical practice, 91% (39/43) for good clinical laboratory practice and 91% (48/53) for infection prevention and control. Platform-based research, developed as part of capacity-building activities for specific projects, may be a valuable tool in fighting future infectious diseases and in developing high-level research in Africa

A phase 2A trial of the safety and tolerability of increased dose rifampicin and adjunctive linezolid, with or without aspirin, for human immunodeficiency virus-associated tuberculous meningitis: the LASER-TBM trial

Background: Drug regimens that include intensified antibiotics alongside effective anti-inflammatory therapies may improve outcomes in tuberculous meningitis (TBM). Safety data on their use in combination and in the context of human immunodeficiency virus (HIV) are needed to inform clinical trial design. Methods: We conducted a phase 2, open-label, parallel-design, randomized, controlled trial to assess the safety of high-dose rifampicin, linezolid, and high-dose aspirin in HIV-associated TBM. Participants were randomized (1.4:1:1) to 3 treatment arms (1, standard of care [SOC]; 2, SOC + additional rifampicin [up to 35 mg/kg/d] + linezolid 1200 mg/d reducing after 28 days to 600 mg/d; 3, as per arm 2 + aspirin 1000 mg/d) for 56 days, when the primary outcome of adverse events of special interest (AESI) or death was assessed. Results: A total of 52 participants with HIV-associated TBM were randomized; 59% had mild disease (British Medical Research Council (MRC) grade 1) vs 39% (grade 2) vs 2% (grade 3). AESI or death occurred in 10 of 16 (63%; arm 3) vs 4 of 14 (29%; arm 2) vs 6 of 20 (30%; arm 1; P = .083). The cumulative proportion of AESI or death (Kaplan–Meier) demonstrated worse outcomes in arm 3 vs arm 1 (P = .04); however, only 1 event in arm 3 was attributable to aspirin and was mild. There was no difference in efficacy (modified Rankin scale) between arms. Conclusions: High-dose rifampicin and adjunctive linezolid can safely be added to the standard of care in HIV-associated TBM. Larger studies are required to determine whether potential toxicity associated with these interventions, particularly high-dose aspirin, is outweighed by mortality or morbidity benefit. Clinical Trials Registration: NCT03927313