MON-092 Treatment of Cushing Disease in Pregnancy Using Osilodrostat

Abstract Disclosure: M. Aoun: None. A. Razzeto: None. C.V. Villabona: None. Introduction: Cushing Disease during pregnancy is associated with significant maternal and fetal morbidity and mortality. Currently, no human data exist on the safety of osilodrostat, an 11β-hydroxylase inhibitor, during pregnancy. This report describes the first known case of osilodrostat use in pregnancy, resulting in the healthy delivery of a baby. Case Presentation: A 40-year-old woman with recurrent Cushing Disease due to a corticotroph adenoma presented after a failed second transsphenoidal resection. Persistent hypercortisolism and postoperative arginine vasopressin (AVP) deficiency required treatment with Osilodrostat and desmopressin. Two months later, she conceived naturally. At pregnancy diagnosis, alternative treatments were discussed, but the patient chose to continue Osilodrostat. Her care was overseen by a multidisciplinary team, with regular monitoring of cortisol levels, electrolytes, blood pressure, weight, glycemic control, and fetal biometrics. Osilodrostat dosing was adjusted based on trimester-specific cortisol targets and maternal-fetal health, with a maximum dose of 5 mg twice daily. The pregnancy was complicated by placenta previa. The patient was hospitalized twice for self-limiting vaginal bleeding—once in the second trimester and again at 35 weeks. Both episodes resolved spontaneously. Betamethasone was administered for fetal lung maturation. Adjustments to desmopressin were made to manage AVP deficiency throughout pregnancy. At 36 weeks, the patient underwent cesarean delivery, giving birth to a healthy baby boy. She received stress-dose steroids postoperatively and was discharged on her pre-pregnancy Osilodrostat dose (2 mg twice daily) and as-needed desmopressin. The newborn showed no signs of adrenal insufficiency, cortisol excess, or hyperandrogenism. Conclusion: This case demonstrates the successful use of Osilodrostat for managing Cushing Disease during pregnancy, suggesting its potential as a therapeutic option when standard treatments are ineffective or contraindicated. Close maternal and fetal monitoring, along with trimester-specific dose adjustments, ensured safety. While this case resulted in the delivery of a healthy infant, further research is needed to evaluate the safety and long-term outcomes of Osilodrostat use in pregnancy. The case highlights the importance of individualized care and multidisciplinary collaboration in managing rare endocrine disorders during pregnancy. Presentation: Monday, July 14, 2025