All-case post-marketing surveillance of delamanid for treating multidrug-resistant pulmonary tuberculosis in Japan

Background Delamanid is a nitro-dihydro-imidazooxazole derivative that possesses highly potent activity against Mycobacterium tuberculosis, including strains linked to multidrug-resistant tuberculosis (MDR-TB). We conducted an all-case post-marketing surveillance to assess the real-world safety and effectiveness of delamanid in treating MDR-TB in Japan. Methods All patients diagnosed with MDR-TB were included if they started delamanid between September 2014 and February 2023. Case report forms were collected every 6 months during the treatment period and every 12 months during the follow-up period. Safety assessment included any adverse events that occurred during the treatment period. Effectiveness assessment included the proportion of patients with sputum-culture conversion and treatment success. Results In the safety analysis set, 61.6 % of patients (114/185) were males, and the median (interquartile range) age was 48.0 (32.0, 64.0) years. During the treatment period, 54.05 % of patients (100/185) experienced adverse drug reactions (ADRs), and 8.65 % (16/185) experienced serious ADRs. Electrocardiogram QT prolongation was reported in 8.65 % of patients (16/185) but was not associated with an increased risk of cardiovascular events. In the sputum-culture conversion analysis set, sputum-culture conversion was achieved in 86.0 % of patients (80/93). In the effectiveness analysis set, treatment success was achieved in 54.1 % of patients (99/183) by the end of the treatment period. Conclusions This surveillance showed the effectiveness of ≥6 months of delamanid treatment among patients with MDR-TB in real-world settings in Japan, with no new safety issues identified.