The coadministration of rifapentine and raltegravir was evaluated in healthy volunteers who received raltegravir alone (400 mg twice daily), raltegravir (400 mg twice daily) plus rifapentine (900 mg once weekly) and raltegravir (400 mg twice daily) plus rifapentine 600 mg once daily). Coadministration of raltegravir and weekly rifapentine increased raltegravir AUC and Cmax by 71% and 89%, respectively, whereas Cmin decreased by 12%. Coadministration of raltegravir with daily rifapentine did not change raltegravir AUC or Cmax but decreased Cmin by 41%. The increase in raltegravir observed with once weekly rifapentine was safe. Once weekly rifapentine (for treatment of latent TB) can be used with raltegravir without dose adjustment. However, the proper dosing strategy of daily rifapentine (for treatment of active TB) is still under clinical investigation.
Pharmacokinetic interaction of rifapentine and raltegravir in healthy volunteers. Weiner M et al. J Antimicrob Chemother, 2014, 69(4): 1079-85.