Randomized comparison of intranasal and transdermal estradiol

Objective: To compare the efficacy and patient acceptability of intranasal versus transdermal 17 beta -estradiol (E2) delivery systems for postmenopau sal symptoms. Methods: Postmenopausal women were randomly assigned to intranasal 17 beta -E2, 300 mug daily (n = 176) or transdermal 17 beta -E2 (delivering 50 mug/ day), two patches per week (n = 185) for 12 weeks, followed by a 4-week per iod with the alternate treatment. Efficacy was compared between groups usin g the Kupperman Index and vasomotor symptoms at week 12. Patient acceptabil ity was compared by patient choice of administration route and by questionn aire at week 16. Results: Intranasal and transdermal therapy produced significant reductions in the Kupperman Index and in the occurrence of hot flushes and night swea ts at week 12. Alleviation of climacteric symptoms was statistically equiva lent in the two treatment groups (P <.001). The difference between groups i n the Kupperman Index score of -0.5 +/- 0.9 (95% confidence interval -2.3, 1.3) was rvithin the predetermined interval of equivalence. Both therapies were well tolerated with similar adverse event rates, except for moderate a nd severe mastalgia which was significantly less frequent with intranasal E 2 (7.2%) than with the patch (15.5%, P =.02). Sixty-six percent of patients chose to continue the intranasal therapy and 34% the transdermal therapy ( P <.001). Satisfaction was greater with intranasal therapy at week 16 (P <. 001). Conclusion: Intranasal and transdermal estrogen delivery systems had equiva lent efficacy and similar safety profiles. Intranasal therapy was the patie nts' choice for long-term treatment. (Obstet Gynecol 2000;96:906-12. (C) 20 00 by The American College of Obstetricians and Gynecologists.).