Introducing new and repurposed TB drugs: the endTB experience

In 2015, the initiative Expand New Drug Markets for TB (endTB) began, with the objective of reducing barriers to access to the new and repurposed TB drugs. Here we describe the major implementation challenges encountered in 17 endTB countries. We provide insights on how national TB programmes and other stakeholders can scale-up the programmatic use of new and repurposed TB drugs, while building scientific evidence about their safety and efficacy. For any new drug or diagnostic, multiple market barriers can slow the pace of scale-up. During 2015-2019, endTB was successful in increasing the number of patients receiving new and repurposed TB drugs in 17 countries. The endTB experience has many lessons, which are relevant to country level introduction of new TB drugs, as well as non-TB drugs and diagnostics. For example: the importation of TB drugs is possible even in the absence of registration; emphasis on good clinical monitoring is more important than pharmacovigilance reporting; national guidelines and expert committees can both facilitate and hinder innovative practice; clinicians use new and repurposed TB drugs when they are available; data collection to generate scientific evidence requires financial and human resources; pilot projects can drive national scale-up.

Is 6 months of bedaquiline enough? Results from the compassionate use of bedaquiline in Armenia and Georgia

BACKGROUND AND SETTING

Bedaquiline (BDQ) was initially only available through compassionate use programmes.

OBJECTIVE

To assess the effectiveness and safety of multidrug-resistant tuberculosis (MDR-TB) treatment containing BDQ.

METHOD

Retrospective analysis of data from patients receiving BDQ through compassionate use in Armenia and Georgia from April 2013 to April 2015. Logistic regression was used to assess the risk factors associated with unsuccessful treatment outcomes.

RESULTS

Of 82 patients included, 84.2% (69/82) had fluoroquinolone-resistant MDR-TB and 43.4% (23/53) were seropositive for the hepatitis C virus (HCV). The culture conversion rate was 84.4% (54/64), and 18.5% (10/54) reverted back to positive. In total, 79.3% (65/82) of the patients reported at least one adverse event. Serious adverse events were reported in 14 patients, with 10/14 patients experiencing fatal outcomes-6/10 related to advanced TB and 2/10 assessed as possibly related to BDQ. Treatment outcomes were as follows: 58.5% treatment success, 12.2% deaths, 7.3% failures and 21.9% lost to follow-up. HCV coinfection was associated with unsuccessful outcomes (adjusted OR 4.45, 95%CI 1.23-16.13).

CONCLUSION

BDQ through compassionate use showed relatively good success rates and safety profiles in a cohort with difficult-to-treat MDR-TB. High rates of reversion may indicate that >24 weeks of BDQ is necessary in some cases. HCV coinfection should be diagnosed and treatment considered in MDR-TB patients.

The thin-layer agar method for direct phenotypic detection of multi- and extensively drug-resistant tuberculosis

BACKGROUND

Molecular techniques rapidly detect resistance to rifampicin (RMP) and isoniazid (INH), but do not eliminate the need for culture-based drug susceptibility testing (DST) against other drugs. The thin-layer agar (TLA) test, a non-commercial direct DST method, has demonstrated good performance for INH and RMP; however, evidence is still limited, and its applicability for DST of ofloxacin (OFX) and kanamycin (KM) is unknown.

DESIGN

We compared 279 TLA DST results with those of MGIT for INH and RMP, and 280 results for OFX and KM with those of the 7H11 agar proportion method, obtained from 320 smear-positive samples from 165 Georgian TB patients. Discrepancies were solved by comparison with a composite reference standard. The prevalence of multidrug-resistant tuberculosis (TB) was 30 of 164 patients (18.3%), 2 (6.7%) of whom had extensively drug-resistant TB.

RESULTS

TLA showed 94.7%, 98.2%, 100% and 78.9% sensitivity, respectively, for INH, RMP, OFX and KM, with 100% specificity. Average time to results was 7 days in TLA, 23 in MGIT and 49 for 7H11 agar.

CONCLUSIONS

In low-resource settings, TLA can be applied for the rapid detection of resistance to INH, RMP and fluoroquinolones. Further studies are necessary to improve sensitivity to KM and further assess its performance for OFX and other drugs and its applicability in field conditions.