Phase I/II trial with fozivudine tidoxil (BM 21.1290): a 7 day randomized, placebo-controlled dose-escalating trial.

BACKGROUND AND OBJECTIVES: A Phase I dose-escalating trial with single doses of fozivudine tidoxil (BM21.1290; FZD), in vitro, and experimental in vivo data indicated that further investigations with this compound were warranted. Advantages of fozivudine tidoxil are the direct delivery of zidovudine monophosphate intracellularly and high concentrations in lymphatic tissues. Our objectives were to evaluate safety, tolerability and efficacy of fozivudine tidoxil in human immunodeficiency virus (HIV)-infected patients. PATIENTS AND METHODS: In a Phase I/II dose-escalating trial, three doses of fozivudine tidoxil (400, 800 or 1200 mg/day) were administered for 1 week. The study was randomized and placebo controlled. Inclusion criteria were HIV infection, CD4 count > 100 cells/mm3 and informed consent. The exclusion criteria were active opportunistic infection and prior antiretroviral treatment.
RESULTS: The tolerability of fozivudine tidoxil was excellent in all dose groups. No treatment discontinuations were necessary. Steady-state pharmacokinetics did show slightly higher concentrations as compared with levels after the first dose (20%). Viral load reduction was most pronounced in the 1200 mg/day dose group (-0.64 log). No viral load reduction was seen in the placebo group.
CONCLUSIONS: The zidovudine conjugate fozivudine tidoxil is safe and well tolerated at the three doses tested. Based on the differences in molecular weights, the 1200 mg dose is roughly equivalent to 400 mg zidovudine.

RCT Entities:   Population Interventions Outcomes