A randomized comparative study of the metabolic effects of two regimens of gestrinone in the treatment of endometriosis.

Objective: To study some of the metabolic effects of oral gestrinone on plasma lipoprotein risk markers for cardiovascular disease and on bone density, a risk marker for osteoporosis.
Design: Randomized double-blind study.
Setting: All patients were referred to Gynaecology Clinic of Royal Free Hospital Medical School.
Patients: Twenty premenopausal women with laparoscopically confirmed endometriosis.
Interventions: Subjects were randomized in a double-blind fashion to receive either 1.25 mg or 2.5 mg gestrinone two times per week for 6 months.
Main Outcome Measure: Laparoscopy was performed before treatment, and clinical responses were determined by second laparoscopy after 6 months. Plasma lipid and bone density measurements during and after therapy were compared with baseline.
Result: Median total endometriosis scores decreased from 7.5 to 1.0 in the 1.25-mg group and from 7.0 to 0 in the 2.5-mg group. There were no significant between-group differences in endometriosis scores. At both doses, bone density in the spine and the proximal femur was conserved, but plasma concentrations of low-density lipoproteins rose by 13% and those of high-density lipoproteins fell by 40%.
Conclusions: Reducing the dose of gestrinone to 1.25 mg appeared to maintain the therapeutic effectiveness of this treatment but was still associated with potentially unfavorable effects on lipids and lipoproteins.