Efficacy, safety, and completion of modified short-course rifapentine and isoniazid for latent tuberculosis infection in patients with high-risk rheumatic disease: a multicentre, open-label, randomized, non-inferiority trial.

BACKGROUND: Patients with rheumatic diseases are at high risk for latent tuberculosis infection (LTBI) reactivation. We aimed to evaluate whether a modified 3-month regimen (3HP-PUMCH) was non-inferior to the standard 9-month isoniazid regimen (9H) for tuberculosis preventive treatment in this vulnerable population.

METHODS: We conducted a multicenter, open-label, randomized, non-inferiority trial at nine tertiary general hospitals in China. Eligible participants were adults (18-70 years) with high-risk rheumatic diseases and LTBI undergoing immunosuppressive therapy. Patients were randomized (1:1) to receive either the 3HP-PUMCH regimen (twice-weekly rifapentine 450 mg plus daily isoniazid 300 mg) or the 9H regimen (daily isoniazid 300 mg). The primary endpoint was the occurrence of tuberculosis, with a non-inferiority margin of 1.4 percentage points. Analysis used the modified intention-to-treat population. The trial was registered with Chinese Clinical Trial Registry ChiCTR1800018242.

FINDINGS: Between 19 September 2018 and 18 August 2021, 536 patients with rheumatic diseases were enrolled. The cumulative rate of tuberculosis was 0.00% (0 of 249, 95% CI 0.00-1.47) in the 3HP-PUMCH group, compared with 1.15% (3 of 260, 95% CI 0.24-3.34) in the 9H group, with a rate difference of -1.15 percentage points (95% CI -2.4 to 0.14). Drug discontinuation rates due to serious adverse events or tuberculosis occurrence were 2.8% (7 of 249) in the 3HP-PUMCH group and 1.9% (5 of 260) in the 9H group (p = 0.509). Adverse drug reactions occurred in 24 (9.6%) of 249 patients versus 39 (15.0%) of 260 (p = 0.066), with hepatotoxicity in 11 (4.4%) of 249 versus 27 (10.4%) of 260 (p = 0.010). 223 (89.6%) of 249 patients completed treatment in the 3HP-PUMCH and 237 (91.2%) of 260 in the 9H group (p = 0.54).

INTERPRETATION: The short-course 3HP-PUMCH regimen was non-inferior to the 9H regimen in preventing tuberculosis and demonstrated a favorable safety profile, with high treatment completion in LTBI patients with rheumatic diseases. This regimen might be more suitable for patients with underlying diseases and those on concomitant medications.

FUNDING: National Natural Science Foundation of China.