Effectiveness and safety of the BPaL regimen in the Philippines

Treatment success among multidrug-resistant/rifampicin-resistant TB (MDR/RR-TB) patients in the Philippines increased with the introduction of a 9-month all-oral treatment regimen; however, this remained sub-optimal, and patients continued to endure the burdensome and toxic effects of component medicines. In 2022, the World Health Organization recommended a 6-month MDR-TB regimen (bedaquiline, pretomanid, and linezolid or BPaL given for 26 weeks).

Operational research was conducted in 12 TB treatment centers in 10 regions in the Philippines using the BPaL regimen. From June 2021 to December 2022, patients with pre-extensively drug-resistant TB or MDR/RR-TB that was treatment intolerant or nonresponsive to a previous MDR-TB regimen were enrolled. Linezolid was started daily at either 1200 mg or 600 mg.

A total of 103 patients received the BPaL regimen; 96 patients were included in the cohort analysis. Despite fluoroquinolone resistance in 42 %, cavitary TB 31 %, diabetes mellitus 42 %, and HIV coinfection 8 %, treatment success was 98 %, with 1 (1 %) death and 1 (1 %) patient not evaluated. Sputum culture conversion was 78 % at month 1 of treatment, and 96 % by month 4. Sustained success at 6 and 12 months post-treatment were 92 % and 90 %, respectively, with the remainder attributable to patients not returning for post-treatment follow-up.Adverse events were mostly grade 1-2, which fully resolved in almost all patients. Linezolid dose modifications, and BPaL regimen interruption occurred in 66 % and 18 %, respectively.

The BPaL regimen had a remarkably high treatment success, rapid culture conversion, and a manageable safety profile among MDR/RR-TB patients in this study despite fluoroquinolone resistance and comorbidities.