- Podany, Anthony T;
- Pham, Michelle;
- Sizemore, Erin;
- Martinson, Neil;
- Samaneka, Wadzanai;
- Mohapi, Lerato;
- Badal-Faesen, Sharlaa;
- Dawson, Rod;
- Johnson, John L;
- Mayanja, Harriet;
- Lalloo, Umesh;
- Whitworth, William C;
- Pettit, April;
- Campbell, Kayla;
- Phillips, Patrick PJ;
- Bryant, Kia;
- Scott, Nigel;
- Vernon, Andrew;
- Kurbatova, Ekaterina V;
- Chaisson, Richard E;
- Dorman, Susan E;
- Nahid, Payam;
- Swindells, Susan;
- Dooley, Kelly E;
- Fletcher, Courtney V
Background
A 4-month regimen containing rifapentine and moxifloxacin has noninferior efficacy compared to the standard 6-month regimen for drug-sensitive tuberculosis. We evaluated the effect of regimens containing daily, high-dose rifapentine on efavirenz pharmacokinetics and viral suppression in patients with human immunodeficiency virus (HIV)-associated tuberculosis (TB).Methods
In the context of a Phase 3 randomized controlled trial, HIV-positive individuals already virally suppressed on efavirenz--containing antiretroviral therapy (ART) (EFV1), or newly initiating efavirenz (EFV2) received TB treatment containing rifapentine (1200 mg), isoniazid, pyrazinamide, and either ethambutol or moxifloxacin. Mid-interval efavirenz concentrations were measured (a) during ART and TB cotreatment (Weeks 4, 8, 12, and 17, different by EFV group) and (b) when ART was taken alone (pre- or post-TB treatment, Weeks 0 and 22). Apparent oral clearance (CL/F) was estimated and compared. Target mid-interval efavirenz concentrations were > 1 mg/L. Co-treatment was considered acceptable if > 80% of participants had mid-interval efavirenz concentrations meeting this target.Results
EFV1 and EFV2 included 70 and 41 evaluable participants, respectively. The geometric mean ratio comparing efavirenz CL/F with vs without TB drugs was 0.79 (90% confidence interval [CI] .72-.85) in EFV1 and 0.84 [90% CI .69-.97] in EFV2. The percent of participants with mid-interval efavirenz concentrations > 1mg/L in EFV1 at Weeks 0, 4, 8, and 17 was 96%, 96%, 88%, and 89%, respectively. In EFV2, at approximately 4 and 8 weeks post efavirenz initiation, the value was 98%.Conclusions
TB treatment containing high-dose daily rifapentine modestly decreased (rather than increased) efavirenz clearance and therapeutic targets were met supporting the use of efavirenz with these regimens, without dose adjustment.Clinical trials registration
NCT02410772.