Increased bactericidal activity but dose-limiting intolerability at 50 mg.kg(-1) rifampicin

Brake, Lindsey H. M. te; de Jager, Veronique; Narunsky, Kim; Vanker, Naadira; Svensson, Elin M.; Phillips, Patrick P. J.; Gillespie, Stephen H.; Heinrich, Norbert; Hoelscher, Michael; Dawson, Rodney; Diacon, Andreas H.; Aamoutse, Rob E. und Boeree, Martin J. (2021): Increased bactericidal activity but dose-limiting intolerability at 50 mg.kg(-1) rifampicin. In: European Respiratory Journal, Bd. 58, Nr. 1, 2000955

Abstract

Accumulating data have indicated that higher rifampicin doses are more effective and shorten tuberculosis treatment duration. This study evaluated the safety, tolerability, pharmacokinetics, and 7 and 14-day early bactericidal activity (EBA) of increasing doses of rifampicin. Here we report the results of the final cohorts of PanACEA HIGHRIF1, a dose-escalation study in treatment-naive adult smear-positive patients with tuberculosis. Patients received, in consecutive cohorts, 40 or 50mg/kg rifampicin once daily in monotherapy (day 1-7), supplemented with standard dose isoniazid, pyrazinamide and ethambutol between day 8-14. In the 40mg/kg cohort (n=15), 13 patients experienced a total of 36 adverse events (AEs) during monotherapy, resulting in one treatment discontinuation. In the 50mg/kg group (n=17), all patients experienced AEs during monotherapy, 93 in total;11 patients withdrew or stopped study medication. AEs were mostly mild/moderate and tolerability-rather than safety-related, i.e. gastrointestinal disorders, pruritis, hyperbilirubinemia and jaundice. There was a more than proportional increase in the rifampicin geometric mean AUC(0-24h) for 50mg/kg compared to 40mg/kg;571 mg/L*h (range 320-995) versus 387 mg/L*h (201-847), while peak exposures saw proportional increases. Protein-unbound exposure after 50mg/kg (11%, 8-17%) was comparable with lower rifampicin doses. Rifampicin exposures and bilirubin concentrations were correlated (day-3 Spearman's rho 0.670, p<0.001). EBA increased considerably with dose, with the highest seen after 50mg/kg;14-day EBA -0.427 logCFU/mL/day (95%CI -0.500, -0.355). In conclusion, although associated with an increased bactericidal effect, the 50mg/kg dose was not well tolerated. Rifampicin at 40mg/kg was well tolerated and therefore selected for evaluation in a phase IIC treatment shortening trial.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Medizin
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• ISSN: 0903-1936
• Sprache: Englisch