Prolonged adrenocortical blockade following discontinuation of Osilodrostat.

Introduction: Osilodrostat is the newest approved steroidogenic inhibitor drug for the treatment of hypercortisolism. In this article, we describe 3 patients who experienced a previously undescribed adverse event: a prolonged adrenocortical blockade following treatment cessation.

Methods: Patient records showing a history of successful hypercortisolism control with Osilodrostat followed by at least 4 weeks of treatment interruption were reviewed. Patient characteristics and hormonal dosage were analyzed.

Results: Persistence of adrenocortical blockade was found in 3 patients and lasted from 6 weeks to 9 months depending on patients. This phenomenon manifested in patients regardless of lower or higher daily Osilodrostat doses (2-10 mg) and total treatment duration did not seem to predict the severity of the blockade.

Conclusion: The finding of this previously undescribed side effect highlights the importance of continuing adrenal function monitoring after Osilodrostat interruption to prevent adrenal crisis in patients at risk.