Theranekron for treatment of endometriosis in a rat model compared with medroxyprogesterone acetate and leuprolide acetate

Abstract Objectives The aim of this study was to compare the effects of theranekron, medroxyprogesterone acetate (MPA), and leuprolide acetate (LA) on surgically induced endometriosis in a rat model. Study design Endometriosis was surgically induced in forty female rats during estrus. After 3 weeks, a second operation was performed and the rats were randomized using a randomization table into theranekron, MPA, LA, and control groups. These treatments were continued for 3 weeks. A third operation was performed to evaluate treatment results. Then, the experimental treatments were halted and estrogen was initiated again to maintain estrus. After three additional weeks; i.e. after 9 weeks, the recurrence rate of endometrial foci was evaluated in a fourth operation and the rats were sacrificed. The volume of endometriotic foci and histopathology scores before and after treatment were compared. Results The respective mean volumes of the endometriotic foci after 3, 6, and 9 weeks were 86.4 ± 21.2, 16.4 ± 8.2, and 20.1 ± 9.6 mm3 in the theranekron group, 78.3 ± 20.4, 42.6 ± 13.5, and 66.7 ± 16.2 mm3 in the MPA group, and 91.8 ± 30.2, 34.4 ± 11.4, and 72.4 ± 21.9 mm3 in the LA group. The respective mean histopathology scores were 2.4 ± 0.6, 1.8 ± 0.6, and 1.6 ± 0.6 in the theranekron group, 2.5 ± 0.8, 2.0 ± 1.1, and 2.7 ± 1.0 in the MPA group, and 2.3 ± 0.5, 2.1 ± 1.2, 2.4 ± 0.8 in the LA group. After 9 weeks, the mean volume of endometriotic foci and histopathology scores were significantly lower in the theranekron group. Conclusions Theranekron caused more evident regression of endometriotic foci than MPA or LA in a rat model. After stopping the theranekron treatment, the recurrence rate was also lower than that of the other groups.