Comparison of the effect of levonorgestrel-intrauterine system with or without oral megestrol acetate on fertility-preserving treatment in patients with atypical endometrial hyperplasia: A prospective, open-label, randomized controlled phase II study

Objective. To compare the effects of levonorgestrel-intrauterine system (LNG-IUS) with or without oral megestrol acetate (MA) versus MA alone on fertility-preserving treatment in patients with atypical endometrial hyperplasia (AEH). Methods. This was a single-center phase II study with an open-label, randomized, controlled trial conducted between July 2017 and June 2020 at the Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China. A total of 180 patients (18-45 years) with primary AEH were randomly assigned (1:1:1) to the MA (N = 60), LNG-IUS (N = 60), or MA + LNG-IUS (N = 60) groups, in which the patients received MA (160 mg orally daily), LNG-IUS, or MA + LNG-IUS (MA 160 mg orally daily plus LNG-IUS), respectively. The primary endpoint was complete response (CR) rate at 16 weeks of treatment. The secondary endpoints were CR rate at 32 weeks of treatment, adverse events, and recurrence and pregnancy rates. All analyses were conducted in a modified intention to treat (ITT) population who underwent randomization and in whom treatment was initiated. Results. The Kaplan-Meier estimate of 16-week CR rates (with 95% confidence interval) were 19.2% (9.0-29.4%) in the MA group, 35.0% (22.8-47.2%) in the LNG-IUS group, and 29.4% (17.2-41.6%) in the MA + LNG-IUS groups. Side effects such as weight gain, increased nocturnal urine, night sweat, insomnia and edema face seemed to occur less frequently in LNG-IUS group compared with MA group. No difference was found among groups regarding second endpoints. Conclusions. LNG-IUS or LNG-IUS plus MA did not show significant therapeutic benefit compared with MA alone. Further studies including sufficient sample-size are needed to validate these findings due to the underpowered design of this trial. Funding. This study was supported by the National Key Research and Development Program of China (Grant No 2019YFC1005200 and 2019YFC1005204), Shanghai Medical Centre of Key Programs for Female Reproductive Diseases (Grant No. 2017ZZ010616), Shanghai sailing program (Grant No. 19YF1404200), and Shen Kang clinical project (SHDC22021219).