NCT06318416

Precision Rifampin Trial for Personalized Dosing

Precision Rifampin (P-RIF) Trial for Personalized Dosing in Active Tuberculosis Disease

• Status: Recruiting
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 200 (estimated)
• Sponsor: University of Virginia · Academic / Other
• Sex: All
• Age: 3 Years
• Healthy volunteers: Not accepted

Summary

Individual pharmacokinetic variability is an important driver of tuberculosis (TB) treatment failure particularly among undernourished populations, and that suboptimal serum drug concentrations are associated with delayed response to treatment, death, and acquired bacterial drug resistance. Serum drug exposures can be approximated by urine excretion as measured by spectrophotometry, replacing the need for specialized equipment for serum testing. Anti-TB pharmacokinetic variability has also been associated with enteric pathogen burden. The overall hypothesis is that urine spectrophotometry will identify people with below-target rifampin serum concentrations, which can be corrected to target levels after dose adjustment as confirmed by serum mass spectrometry. Therefore, this protocol includes a clinical trial to assess efficacy and safety of rifampin dose adjustment based on urinary excretion levels among adults and children who are being treated for drug-sensitive pulmonary TB at our longstanding collaborative research site in Haydom Lutheran Hospital, Tanzania.

Detailed description

This is a single-site trial at Haydom Lutheran Hospital, a regional referral hospital level in Manyara Region of northern Tanzania. The primary objective: Among children and adults in Tanzania initiating treatment for drug-susceptible pulmonary TB, perform urine spectrophotometric testing for rifampin, and collect serum throughout the 24 hour dosing interval for later concentration measurement by gold-standard mass spectrometry and comparative pharmacokinetics. Patients with urine rifampin excretion below target will undergo incremental dose increase and urine spectrophotometry and serum collection will be repeated. Stool will also be evaluated at regular intervals to understand the association with enteropathogen burden and effects on rifampin absorption, urine excretion, and serum exposures. Participants will randomized to an early group where urine spectrophotometry and dose adjustment is performed at Day 14 after treatment initiation, or a delayed group where the intervention is performed at Day 21. Primary efficacy endpoint is the proportion of subjects in the early and delayed groups that reach serum target AUC0-24 (35 ug/mL for adults; 31.7 ug/mL for children) at Day 21, before the urine based dose adjustment is made in the delayed group. Primary safety endpoint is the number of severe adverse events. Secondary endpoints include: time to sputum culture conversion to negative, weight change. Time to culture conversion and weight change are stratified by age given pediatric populations are more likely to be culture negative and clinically diagnosed with weight gain a central measurement of treatment response. Safety of dose adjustment strategy parameters include clinical adverse events, liver function tests, kidney function tests and hematological parameters

Conditions

• Tuberculosis

Interventions

Type	Name	Description
DIAGNOSTIC_TEST	urine spectrophotometry for rifampin absorbance	All participants will received conventional weight-based TB therapy, standard of care for active TB disease. After enrollment, participants will be randomized to early Day 14 or delayed Day 21 dose modification of rifampin informed by urine spectrophotometry where absorbance is determined above or below a threshold. Below a threshold, single tablets of rifampin are added to conventional fixed drug combination standard of care, above a threshold, no additional rifampin is added. Dose adjustment of rifampin may be up to \~30mg/kg and will be continued through day-56.

Timeline

• Start date: 2025-10-01
• Primary completion: 2027-12-30
• Completion: 2028-06-01
• First posted: 2024-03-19
• Last updated: 2026-01-27

Locations

1 site across 1 country: Tanzania