Effects of vehicle supplementation on total estradiol absorption from a transdermal estradiol delivery system**Supported by a grant from Besins-Iscovesco, Paris, France.††Presented at the 45th Annual Meeting of The American Fertility Society, San Francisco, California, November 11 to 16, 1989

Bioavailability of oestradiol from the Alora TM (0.1 mg/day) oestradiol matrix transdermal delivery system compared with Estraderm (0.1 mg/day)

This open-label, randomised, two-way crossover study compared the steady-state bioavailability of oestradiol administered by way of a new oestradiol matrix transdermal delivery system (Alora 0.1 mg/day) with that of Estraderm (0.1 mg/day) in 24 subjects. Serum oestradiol, oestrone and oestrone sulphate concentrations were determined by measurement of blood samples. Mean SD pre-dosing, nonadjusted oestradiol levels for Alora (71.9 27.0 pg/ml) were substantially higher than those for Estraderm (26.7 9.7 pg/ml), while peak oestradiol concentrations were comparable. Consequently, fluctuations in steady-state levels were substantially smaller for Alora than for Estraderm; the fluctuation index values (\[C- C ])/ max min C ) were significantly lower for Alora (0.97 0.23) than av for Estraderm (1.68 0.45). Oestradiol levels remained constant over the dosing interval with Alora but decreased significantly after 48 hours with Estraderm. The bioavailability of oestradiol with Alora was 127 56% that of Estraderm. Oestrone and oestrone sulphate data showed the same qualitative and quantitative differences between the two systems. Both systems were well tolerated. In summary, Alora delivered more oestradiol to the systemic circulation with greater consistency and over a longer time than did Estraderm.

Initial and steady-state pharmacokinetics of a vaginally administered formulation of progesterone

OBJECTIVE

The pharmacokinetics of a 100 mg vaginal progesterone suppository was evaluated on days 1 and 7 and a 200 mg suppository on day 14. All the volunteers were given oral 17 beta-estradiol during the study.

STUDY DESIGN

Ten postmenopausal women volunteered for this study. Progesterone was given as a vaginal suppository. Peripheral venous samples were obtained at appropriate intervals and analyzed for 17 beta-estradiol and progesterone levels. Area under the curve for progesterone was assessed by the trapezoidal method. Statistical analysis was performed by a one-way analysis of variance.

RESULTS

Serum 17 beta-estradiol levels ranged from 22 to 182 pg/ml. Maximal serum progesterone levels ranged from 5.7 to 20.9 ng/ml, with the mean maximal levels 13.97, 16.09, and 12.68 ng/ml (not significantly different) and a mean area under the curve of 168.13, 207.64 and 227.71 ng/ml per hour on days 1, 7, and 14 (not statistically different).

CONCLUSIONS

These data indicate that vaginal absorption of progesterone is efficient. The lack of difference in the area under the curve for both doses suggests that the vaginal mucosa or the total surface area of the vagina may limit the absorption of progesterone from the vagina.