Bioequivalence Study of the Oral Contraceptive Tablet Containing Norgestimate (NGM)/Ethinyl Estradiol (EE) With or Without Folic Acid in Healthy Women.

Overview

The purpose of the study is to determine the bioequivalence of NGM and EE in 2 formulations of 250 mcg NGM/35 mcg EE, 1 without folic acid and 1 containing 400 mcg folic acid. The pharmacokinetics of blood folate from the formulation of 250 mcg NGM/35 mcg EE containing 400 mcg folic acid and from 400 mcg folic acid administered alone is characterized.

This is a single-center, open-label, randomized (study drug assigned by chance), 3-way crossover bioequivalence study of a single dose of 250 mcg NGM/35 mcg EE with or without folic acid. The study consisted of a pretreatment phase (a screening period lasting up to 21 days), an open-label treatment phase (consisting of 3 periods during which a single dose of study drug was administered followed by up to 72 hours of serial blood sample collections for pharmacokinetic analysis), and a posttreatment phase (consisting of safety evaluations at the completion of the third open-label treatment period or at early withdrawal). All healthy volunteers received the following treatments (1 during each period): Treatment A: 250 mcg NGM/35 mcg EE; Treatment B: 250 mcg NGM/35 mcg EE plus folic acid 400 mcg (combined formulation); Treatment C: folic acid 400 mcg. Healthy volunteers were randomly assigned to 1 of 6 treatment sequence groups (ABC, ACB, BAC, BCA, CAB, or CBA) on Day 1 of the first open-label treatment period. Healthy volunteers received a single dose of study drug on Day 1 in each period according to their assigned treatment sequence. There was a washout period between treatments of at least 4 weeks. Healthy volunteers were confined to the study unit from the evening before dosing (Day -1) until after vital signs were measured following collection of the 24 hour (Treatment C) or 48-hour (Treatments A or B) postdose blood sample. Blood samples were collected at specified times for 24 hours after dosing for the determination of blood levels of folate and for 72 hours after dosing for the determination of blood levels of norelgestromin (NGMN), and norgestrel (NG) \[the active breakdown products of NGM\], and EE. The total duration of the study, not including the pretreatment phase, was approximately 9 weeks. Safety was evaluated based on the following: the incidence, type, and severity of adverse events; clinical laboratory tests; vital sign and electrocardiogram (ECG) measurements; and physical and gynecological (including breast) examinations. Oral temperature, heart rate, respiratory rate, and blood pressure were measured at screening, before each dose, and at least 15 minutes after the 24-hour (all treatments) and 48- and 72-hour (healthy volunteers who received Treatments A or B) pharmacokinetic blood samples in each period, or at early withdrawal. In Period 3, the end-of-study assessments were considered the 24-hour (for healthy volunteers who received Treatment C) and the 72-hour (for healthy volunteers who received Treatments A and B) measurements. Physical and gynecologic examinations and ECG were performed at screening, and at least 1 hour after the last pharmacokinetic blood sample on Day 58 for healthy volunteers who received Treatment C in Period 3, on Day 60 for healthy volunteers who received Treatments A or B in Period 3, or at early withdrawal. Blood samples for blood chemistry, hematology, and urine samples for urinalysis were collected at screening, after the last pharmacokinetic blood sample on Day 58 for healthy volunteers who received Treatment C in the third treatment period, on Day 60 for healthy volunteers who received Treatments A or B in Period 3, or at early withdrawal. Treatment A (250 mcg NGM/35 mcg EE) was administered as a single tablet corresponding to Days 15 to 21 in the commercial dialpak of oral contraceptives (OC) study drug; Treatment B (250 mcg NGM/35 mcg EE plus 400 mcg of folic acid) was administered as a single tablet; and Treatment C (400 mcg of folic acid) was administered as single United States Pharmacopoeia (USP) tablet.