A pragmatic randomized controlled trial to evaluate the efficacy and safety of an oral short-course regimen including bedaquiline for the treatment of patients with multidrug-resistant tuberculosis in China: study protocol for PROSPECT.

Introduction: The lack of safe, effective, and simple short-course regimens (SCRs) for multidrug-resistant/rifampicin-resistant tuberculosis (MDR/RR-TB) treatment has significantly impeded TB control efforts in China.

Methods: This phase 4, randomized, open-label, controlled, non-inferiority trial aims to assess the efficacy and safety of a 9-month all-oral SCR containing bedaquiline (BDQ) versus an all-oral SCR without BDQ for adult MDR-TB patients (18-65 years) in China. The trial design mainly mirrors that of the "Evaluation of a Standardized Treatment Regimen of Anti-Tuberculosis Drugs for Patients with MDR-TB" (STREAM) stage 2 study, while also incorporating programmatic data from South Africa and the 2019 consensus recommendations of Chinese MDR/RR-TB treatment experts. Experimental arm participants will receive a modified STREAM regimen C that replaces three group C drugs, ethambutol (EMB), pyrazinamide (PZA), and prothionamide (PTO), with two group B drugs, linezolid (LZD) and cycloserine (CS), while omitting high-dose isoniazid (INH) for confirmed INH-resistant cases. BDQ duration will be extended from 6 to 9 months for participants with Mycobacterium tuberculosis-positive sputum cultures at week 16. The control arm will receive a modified STREAM regimen B without high-dose INH and injectable kanamycin (KM) that incorporates experimental arm LZD and CS dosages, treatment durations, and administration methods. LZD (600 mg) will be given daily for ≥ 24 weeks as guided by observed benefits and harm. The primary outcome measures the proportion of participants with favorable treatment outcomes at treatment completion (week 40), while the same measurement taken at 48 weeks post-treatment completion is the secondary outcome. Assuming an α = 0.025 significance level (one-sided test), 80% power, 15% non-inferiority margin, and 10% lost to follow-up rate, each arm requires 106 participants (212 total) to demonstrate non-inferiority.

Discussion: PROSPECT aims to assess the safety and efficacy of a BDQ-containing SCR MDR-TB treatment at seventeen sites across China, while also providing high-quality data to guide SCRs administration under the direction of the China National Tuberculosis Program for MDR-TB. Additionally, PROSPECT will explore the potential benefits of extending the administration of the 9-month BDQ-containing SCR for participants without sputum conversion by week 16.

Trial Registration: ClinicalTrials.gov NCT05306223. Prospectively registered on 16 March 2022 at https://clinicaltrials.gov/ct2/show/NCT05306223?term=NCT05306223&draw=1&rank=1 {2}.