Lack of pharmacokinetic drug-drug interaction between ciclesonide and erythromycin.

Author(s): Nave R, Drollmann A, Steinijans VW, Zech K, Bethke TD

Affiliation(s): ALTANA Pharma AG Konstanz, Germany. ruediger.nave@altanapharma.com

Publication date & source: 2005-06, Int J Clin Pharmacol Ther., 43(6):264-70.

Publication type: Clinical Trial; Clinical Trial, Phase I; Randomized Controlled Trial

OBJECTIVE: To investigate whether systemic exposure to desisobutyrylciclesonide (des-CIC) (the pharmacologically active metabolite of ciclesonide) and erythromycin are affected by combined administration of ciclesonide and erythromycin. METHODS: 18 healthy subjects were enrolled in a Phase 1, open-label, randomized, three-period crossover study. Each subject received ciclesonide (640 microg ex-actuator, equivalent to 800 microg ex-valve, via hydrofluoroalkane metered-dose inhaler) and erythromycin (500 mg PO), separately and in combination, in random order. Blood samples were collected at timed intervals to determine serum concentrations of erythromycin, des-CIC, and ciclesonide using HPLC-MS detection. Adverse events were recorded throughout the study. RESULTS: Combined administration of ciclesonide and erythromycin did not alter the pharmacokinetics (PK) of either drug. The serum concentration vs. time profiles of erythromycin, des-CIC, and ciclesonide were similar when ciclesonide and erythromycin were administered separately or together. In addition, the PK characteristics of erythromycin and des-CIC were equivalent following single or co-administration. Point estimates (90% confidence intervals (CI)) for erythromycin were as follows: AUC0-inf, 0.96 (0.79, 1.18); Cmax, 1.00 (0.84, 1.20); and t1/2, 0.96 (0.83, 1.12). The following point estimates (90% CI) were obtained for des-CIC: AUC0-inf, 1.16 (1.03, 1.30); Cmax, 1.06 (0.98, 1.15); and t1/2, 1.04 (0.96, 1.13). Lack of ciclesonide/erythromycin interaction was demonstrated as the 90% CI of AUC0-inf, Cmax, and t1/2 of both compounds were entirely within the stipulated equivalence range of 0.67 - 1.50. No study drug-related adverse events occurred during this study. CONCLUSIONS: Combined administration of ciclesonide and erythromycin did not alter the PK properties of either drug. Both drugs were safe and well-tolerated. Therefore, systemic exposure to ciclesonide or erythromycin is not increased in patients receiving concomitant therapy.