An open-label, randomized, two-period, two-group, crossover study was conducted in 26 healthy Chinese volunteers under fasted conditions to assess the bioequivalence between two formulations of Anastrozole.

Anastrozole is currently used as first-line treatment in locally advanced or metastatic breast cancer. A generic anastrozole tablet was developed to offer an alternative to the marketed tablet formulation.The aim of the current study was to evaluate the bioequivalence between the test and reference formulations of anastrozole in a single-dose, 2-period, 2-sequence crossover study with a 21-day washout interval. A total of 26 healthy Chinese female volunteers were enrolled and completed the study, after oral administration of a single dose of 1.0-mg test and reference formulations of anastrozole. Blood samples (3 mL) for pharmacokinetic analysis were collected predose and 20min, 40min, 1, 1h20min, 1h40min, 2, 2h20min, 2h40min, 3, 3.5, 4, 7, 12, 24, 48, and 72 hours postdose and were determined by a fully validated high-pressure liquid chromatography-tandem mass spectrometry method. The evaluated pharmacokinetic parameters, including Cmax, AUC0-t, AUC0-∞, were assessed for bioequivalence based on current guidelines.

Inclusion Criteria:

• Healthy Postmenopausal volunteers aged between 18 and 65 years old.
• The body mass index is in the range of 19.0-28.0 kg/m2 (including the critical value). The weight is not less than 45 kg.
• The subjects have no family planning within 6 months and could select contraceptive method.
• Subjects who had not any medical history of cardiovascular, digestive, respiratory, nervous, haemal diseases or hepatic/renal impairment.

Exclusion Criteria:

• Meet the diagnostic criteria for osteoporosis.
• Subjects with vaginal bleeding.
• blood donation, massive blood loss (#400mL) or enrolled in other clinical trials 3 months prior to screening.
• any use of other prescription drugs (including contraceptive) 28 days prior to medication for this study.
• any history of alcohol abuse in the recent 2 years or moderate drinkers (drink more 2 units per day or 14 units per week);
• smoking more than 5 cigarettes per day during the 3 months prior to screening;