People Who Inject Drugs and have tuberculosis: Opioid Substitution Therapy improves treatment outcomes in Ukraine

INTRODUCTION

Opioid substitution therapy (OST) is one of the pillars of harm reduction strategies for People Who Inject Drugs (PWID). It should be an integral part of tuberculosis (TB) care to increase the uptake, compliance and effectiveness of treatment and also curtail risk behaviors. We aimed to compare TB treatment outcomes in relation to OST among PWID in six regions of Ukraine.

METHODOLOGY

A retrospective cohort study using routine programmatic data from centers offering integrated TB and OST (December 2016 - May 2020). OST involved use of methadone or buprenorphine. TB treatment outcomes were standardized.

RESULTS

Of 228 PWID (85% male) diagnosed with TB, 104 (46%) had drug-sensitive and 124 (64%) drug-resistant TB. The majority had pulmonary TB (95%), 64 (28%) were HCV-positive and 179 (78%) were HIV-positive, 91% of the latter were also on antiretroviral therapy. There were 114 (50%) PWID with TB on OST. For drug-sensitive TB (n=104), treatment success was significantly higher (61%) in those on adjunctive OST than those not on OST (42%, P<0.001). Similarly, for drug-resistant TB (n=124) treatment success was also significantly higher when individuals were on OST (43%) compared to when not on OST (26%, P<0.001).

CONCLUSIONS

This operational research study shows that OST is associated with significantly improved treatment success in PWID and can contribute to achieving Universal Health Coverage and the WHO Flagship Initiative "Find.Treat.All. #End TB". We advocate for the scale-up of this intervention in Ukraine.

The Population Pharmacokinetics of Meropenem in Adult Patients With Rifampicin-Sensitive Pulmonary Tuberculosis

Background: Meropenem is being investigated for repurposing as an anti-tuberculosis drug. This study aimed to develop a meropenem population pharmacokinetics model in patients with pulmonary tuberculosis and identify covariates explaining inter-individual variability.

Methods: Patients were randomized to one of four treatment groups: meropenem 2 g three times daily plus oral rifampicin 20 mg/kg once daily, meropenem 2 g three times daily, meropenem 1 g three times daily, and meropenem 3 g once daily. Meropenem was administered by intravenous infusion over 0.5–1 h. All patients also received oral amoxicillin/clavulanate together with each meropenem dose, and treatments continued daily for 14 days. Intensive plasma pharmacokinetics sampling over 8 h was conducted on the 14th day of the study. Nonlinear mixed-effects modeling was used for data analysis. The best model was chosen based on likelihood metrics, goodness-of-fit plots, and parsimony. Covariates were tested stepwise.

Results: A total of 404 concentration measurements from 49 patients were included in the analysis. A two-compartment model parameterized with clearance (CL), inter-compartmental clearance (Q), and central (V1) and peripheral (V2) volumes of distribution fitted the data well. Typical values of CL, Q, V1, and V2 were 11.8 L/h, 3.26 L/h, 14.2 L, and 3.12 L, respectively. The relative standard errors of the parameter estimates ranged from 3.8 to 35.4%. The covariate relations included in the final model were creatinine clearance on CL and allometric scaling with body weight on all disposition parameters. An effect of age on CL as previously reported could not be identified.

Conclusion: A two-compartment model described meropenem population pharmacokinetics in patients with pulmonary tuberculosis well. Covariates found to improve model fit were creatinine clearance and body weight but not rifampicin treatment. The final model will be used for an integrated pharmacokinetics/pharmacodynamics analysis linking meropenem exposure to early bactericidal activity.