Safety and effectiveness of three novel all-oral shortened regimens for rifampicin- or multidrug-resistant tuberculosis in Kazakhstan.

BACKGROUND: In 2019, WHO called for operational research on all-oral shortened regimens for multidrug- and rifampicin-resistant tuberculosis (MDR/RR-TB). We report safety and effectiveness of three nine-month all-oral regimens containing bedaquiline (Bdq), linezolid (Lzd), and levofloxacin (Lfx) and reinforced with cycloserine (Cs) and clofazimine (Cfz), delamanid (Dlm) and pyrazinamide (Z), or Dlm and Cfz. METHODS: We conducted a prospective cohort study of patients initiating treatment for pulmonary MDR/RR-TB under operational research conditions at public health facilities in Kazakhstan. Participants were screened monthly for adverse events. Participants with baseline resistance were excluded from the study and treated with a longer regimen. We analyzed clinically relevant adverse events of special interest in all participants and sputum culture conversion and end-of-treatment outcomes among individuals who were not excluded. RESULTS: Of 510 participants, 41% were women, median age was 37 years (interquartile range: 28-49), 18% had a body mass index <18·5 kg/m2, and 51% had cavitary disease. Three hundred and ninety-nine (78%) initiated Bdq-Lzd-Lfx-Cs-Cfz, 83 (16%) started Bdq-Lzd-Lfx-Dlm-Z, and 28 (5%) initiated Bdq-Lzd-Lfx-Dlm-Cfz. Fifty-eight individuals (11%) were excluded from the study, most commonly due to identification of baseline drug resistance (n = 52; 90%). Among the remaining 452 participants, treatment success frequencies were 92% (95% confidence interval [CI]: 89 to 95), 89% (95%CI: 80 to 94), and 100% (95%CI: 86 to 100) for regimens with Cs/Cfz, Dlm/Z, and Dlm/Cfz respectively. Clinically-relevant adverse events of special interest were uncommon. CONCLUSION: All regimens demonstrated excellent safety and effectiveness, expanding the potential treatment options for patients, providers, and programs.

Safety and Effectiveness Outcomes From a 14-Country Cohort of Patients With Multi-Drug Resistant Tuberculosis Treated Concomitantly With Bedaquiline, Delamanid, and Other Second-Line Drugs.

BACKGROUND: Concomitant use of bedaquiline (Bdq) and delamanid (Dlm) for multi-drug/rifampicin resistant tuberculosis (MDR/RR-TB) has raised concerns about a potentially poor risk-benefit ratio. Yet this combination is an important alternative for patients infected with strains of TB with complex drug resistance profiles or who cannot tolerate other therapies. We assessed safety and treatment outcomes of MDR/RR-TB patients receiving concomitant Bdq and Dlm, along with other second-line anti-TB drugs. METHODS: We conducted a multi-centric, prospective observational cohort study across 14 countries among patients receiving concomitant Bdq-Dlm treatment. Patients were recruited between April 2015 and September 2018 and were followed until the end of treatment. All serious adverse events and adverse events of special interest (AESI), leading to a treatment change, or judged significant by a clinician, were systematically monitored and documented. RESULTS: Overall, 472 patients received Bdq and Dlm concomitantly. A large majority also received linezolid (89.6%) and clofazimine (84.5%). Nearly all (90.3%) had extensive disease; most (74.2%) had resistance to fluoroquinolones. The most common AESI were peripheral neuropathy (134, 28.4%) and electrolyte depletion (94, 19.9%). Acute kidney injury and myelosuppression were seen in 40 (8.5%) and 24 (5.1%) of patients, respectively. QT prolongation occurred in 7 patients (1.5%). Overall, 78.0% (358/458) had successful treatment outcomes, 8.9% died, and 7.2% experienced treatment failure. CONCLUSIONS: Concomitant use of Bdq and Dlm, along with linezolid and clofazimine, is safe and effective for MDR/RR-TB patients with extensive disease. Using these drugs concomitantly is a good therapeutic option for patients with resistance to many anti-TB drugs.