Phase I Study in Healthy Women of a Novel Antimycotic Vaginal Ovule Combining Econazole and Benzydamine

PURPOSE: A novel fixed-dose combination of 150 mg of econazole with 6 mg of benzydamine formulated in vaginal ovules was investigated in a randomised, double-blind, four-parallel group, tolerability, and pharmacokinetic Phase I study in healthy women. METHODS: The fixed-dose combination was compared to econazole and benzydamine single-drug formulations and with placebo after daily applications for 3 consecutive days. Safety and tolerability were evaluated recording the adverse drug reactions, local and general tolerability scores, clinical laboratory assays, and vital signs. Econazole, benzydamine, and its metabolite benzydamine N-oxide pharmacokinetics were investigated after single and multiple applications. RESULTS: Local reactions were generally absent. Pruritus and pain at the application site were infrequently reported. According to the subjects' evaluations, the overall tolerability of the ovules was rated as excellent or good. No significant effect of any treatment on laboratory parameters, vital signs, body weight, vaginal pH, or ECG was observed. Very low econazole, benzydamine, and benzydamine-N-oxide concentrations were measured in plasma, though quantifiable in almost all samples. CONCLUSION: The tested fixed-dose combination showed a good safety profile consistently with the known tolerability of both active substances. In addition, the confirmed low bioavailability of the drugs excludes the possibility of any accumulation effects and limits the risk of undesired systemic effects. This trial is registered at ClinicalTrials.gov with the identifier NCT02720783 last updated on 07 February 2017.