Effective long-term treatment of Cushing's disease with pasireotide: a case report

Cushing's disease is a rare, devastating condition associated with high morbidity and increased mortality. Primary treatment for Cushing's disease is transsphenoidal surgery to remove the pituitary adenoma; however, recurrence can occur in up to 25% of patients. Second-line medical therapies do not directly target the pituitary tumor. Thus, normalization of adrenocorticotropic hormone (ACTH) and inhibition of tumor growth is not usually achieved.

In this case report, we present a de novo patient with a pituitary macroadenoma who was randomized to receive treatment with subcutaneous twice-daily injections of pasireotide 900 μg as part of the double-blind, Phase III CSOM230B2305 clinical trial.

Around one month after treatment initiation, the patient's urinary free cortisol (UFC) level showed a dramatic reduction (from 151.1 to 7.4 μg/24h) necessitating a dose reduction to 600 μg to relieve the symptoms of corticosteroid withdrawal. One month after dose reduction, the patient's UFC levels remained stable and were associated with improvements in clinical signs and symptoms. These improvements continued into the 12-month extension phase following a dose increase to 900 μg and were accompanied by a significant reduction in tumor volume (from 0.797 cm3 at baseline to 0.359 and 0.365 cm3 at months 18 and 24, respectively). UFC remained normalized throughout the extension period. During the study, the patient developed hyperglycemia, which was effectively controlled with diet and then medication.

In this case study, long-term pasireotide treatment as first-line therapy led to normalization of UFC, reduction of tumor volume and significant improvement in the clinical signs and symptoms of Cushing's disease.