Efficacy and safety of mifepristone in patients with uterine fibroids

Objective: To evaluate the efficacy and safety of Gynestril, 50 mg tablet, in patients with symptomatic uterine fibroids in routine clinical practice.

Materials and methods: This was an open, multicenter, non-interventional, prospective study conducted on the basis of seven Russian clinical centers between 2022 and 2023 in order to investigate the therapeutic efficacy and safety of Gynestril in patients with symptomatic uterine fibroids in routine clinical practice (GYNNEO). All patients (n=234) were administered the drug orally, in the form of a single tablet, once a day on days 1-3 of the menstrual cycle for a period of three months (one course of treatment). The efficacy and safety of the treatment were evaluated during the patients’ visits to the centers: before the drug was prescribed, immediately after completing the treatment with its course for three months and three months after completing the treatment. Efficacy was assessed by changes in the volume and largest linear size of the dominant myomatous node and nodes 2 and 3, which were considered to be the second and third nodes in diameter after the dominant node (provided that their initial diameter was less than 1.5 cm), uterine volume, number of visualized nodes, endometrial thickness, resistance index (RI) and blood flow velocity in the nodes, hemoglobin level, dynamics of symptom severity according to the 5-point Likert scale, etc. The incidence and characteristics of adverse and serious events were considered in the safety assessment.

Results: According to the ultrasound data, the volume of the dominant myomatous node decreased by 33% after three months of therapy with Gynestril and by 59.5% after three months of follow-up compared to baseline (pre-treatment) level. A number of other efficacy endpoints also showed positive trends during the study. They included decreases in volume of nodes 2 and 3, uterine volume, maximum linear size of the nodes, increased RI, and decreased blood flow velocity in the nodes. The severity of the symptoms associated with the disease (pain, dyspareunia, and symptoms of compression) was found to decrease with the complete elimination of moderate and severe symptoms after three months of therapy. Half of the patients had amenorrhea after the treatment and it persisted in 101/234 (43%) patients for three months after completing the treatment with Gynestril. During the study, there were 26/226 (11%) adverse events related to treatment.

Conclusion: The study demonstrates that treatment with Gynestril results in a statistically significant decrease in the volume of myomatous nodes after three months of therapy (immediately after the course) and this effect persists for three months following the completion of the course of therapy. Therapy with Gynestril controls and reduces the severity of symptoms of the disease and the amount of menstrual blood loss. The drug is generally well tolerated by patients.