Evaluation of the effects of rifampicin, ketoconazole and erythromycin on the steady-state pharmacokinetics of the components of a novel oral contraceptive containing estradiol valerate and dienogest in healthy postmenopausal women.
Contraception
; 86(4): 337-44, 2012 Oct.
Article
em En
| MEDLINE
| ID: mdl-22445438
ABSTRACT
BACKGROUND:
We evaluated the effects of cytochrome P450 3A4 (CYP3A4) induction and inhibition on steady-state pharmacokinetics of the components of a novel oral contraceptive (OC) containing estradiol valerate (E2V) and dienogest (DNG). STUDYDESIGN:
CYP3A4 induction was assessed in an open-label, one-arm study. Sixteen healthy postmenopausal women received E2V 2 mg/DNG 3 mg (days 1-17) and concomitant rifampicin (600 mg, days 12-16). Ratios of the area under the serum concentration-time curve between 0 and 24 h [AUC(0-24 h)] and maximum serum concentration (C(max)) of E2 and DNG on days 17 and 11 (after and before rifampicin intervention) are presented. CYP3A4 inhibition was investigated in an open-label, parallel-group study in 24 healthy postmenopausal women receiving E2V 2 mg/DNG 3 mg (days 1-14) and concomitant ketoconazole (400 mg, n=12) or erythromycin (500 mg three times daily, n=12) on days 8-14. Mean ratios of AUC(0-24 h) and C(max) of E2 and DNG on days 7 and 14 are presented.RESULTS:
Concomitant administration of rifampicin decreased systemic drug exposure and yielded geometric mean ratios for E2C(max) and AUC(0-24 h) of 75% and 56%, respectively. Corresponding mean ratios for DNG were 48% and 17%, respectively. Ketoconazole coadministration increased systemic drug exposure and yielded ratios of E2 of 165% and 157%, respectively, and ratios of DNG of 194% and 286%, respectively. Erythromycin coadministration also resulted in increased mean C(max) and AUC(0-24 h) of both E2 and DNG. Geometric mean ratios of C(max) and AUC(0-24 h) for E2 were 151% and 133%, respectively. Corresponding ratios for DNG were 133% and 162%, respectively.CONCLUSIONS:
Significant drug-drug interactions are apparent when CYP3A4 modulators are coadministered with the components of a novel OC containing E2V/DNG. Coadministration of CYP3A4 modulators should be avoided where possible, and another type of contraception should be used when coadministration of CYP3A4 inducers like rifampicin is unavoidable.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Rifampina
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Terapia de Reposição de Estrogênios
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Eritromicina
/
Estradiol
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Citocromo P-450 CYP3A
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Cetoconazol
/
Anti-Infecciosos
/
Nandrolona
Tipo de estudo:
Clinical_trials
Limite:
Aged
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Female
/
Humans
/
Middle aged
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article