Long‐term efficacy and safety of once‐monthly pasireotide in Cushing's disease: A Phase III extension study

Objectives Many patients with Cushing's disease (CD) require chronic pharmacotherapy to control their hypercortisolism. We evaluated the efficacy and safety of long‐acting pasireotide during a long‐term extension study in patients with CD.

Design Open‐label extension to a 12‐month Phase III study of long‐acting pasireotide in CD (N = 150; NCT01374906).

Patients Patients with mean urinary free cortisol (mUFC) ≤ upper limit of normal (ULN) or receiving clinical benefit at core study end could continue long‐acting pasireotide during the extension.

Results Eighty‐one of 150 (54.0%) enrolled patients entered the extension. Median overall exposure to pasireotide at study end was 23.9 months; 39/81 (48.1%) patients completed the extension (received ≥ 12 months’ treatment during the extension and could transit to a separate pasireotide safety study). mUFC was ≤ULN in 42/81 (51.9%), 13/81 (16.0%) and 43/81 (53.1%) patients at extension baseline, month (M) 36 and last assessment. Median mUFC remained within normal limits. Median late‐night salivary cortisol was 2.6 × ULN at core baseline and 1.3 × ULN at M36. Clinical improvements were sustained over time. Forty‐two (51.9%) patients discontinued during the extension: 25 (30.9%) before M24 and 17 (21.0%) after M24. Hyperglycaemia‐related AEs occurred in 39.5% of patients. Mean fasting glucose (FPG) and glycated haemoglobin (HbA1c) were stable during the extension, with antidiabetic medication initiated/escalated in some patients. Sixty‐six (81.5%) and 71 (88.9%) patients were classified as having diabetes (HbA1c ≥ 6.5%, FPG ≥ 7.0 mmol/L, antidiabetic medication use, or history of diabetes) at extension baseline and last assessment.

Conclusions Long‐acting pasireotide provided sustained biochemical and clinical improvements, with no new safety signals emerging, supporting its use as an effective long‐term therapy for CD.