Signifor / Signifor LAR (pasireotide)
Pasireotide diaspartate (subcutaneous form); Pasireotide pamoate (long-acting release intramuscular form). Synonyms: SOM230, SOM230C. Chemical name: (2-Aminoethyl) carbamic acid (2R,5S,8S,11S,14R,17S,19aS)-11-(4-aminobutyl)-5-benzyl-8-(4-benzyloxybenzyl)-14-(1H-indol-3-ylmethyl)-4,7,10,13,16,19-hexaoxo-17-phenyloctadecahydro-3a,6,9,12,15,18-hexaazacyclopentacyclooctadecen-2-yl ester, di[(S)-2-aminosuccinic acid] salt (diaspartate form).
Approved status applies to specific products, routes, and indications, not every use context discussed online.
An FDA-approved injectable medication (Signifor) that lowers cortisol (the body's main stress hormone) in Cushing's disease -- a rare condition where a small noncancerous growth on a brain gland causes the body to produce too much cortisol. It was the first drug approved that directly targets the underlying cause of this condition.
Safety Summary
The safety profile of pasireotide is dominated by metabolic effects, particularly hyperglycemia. In the pivotal Phase III Cushing's disease trial (N=162), nearly all patients experienced worsening glycemia within the first 2 weeks of treatment, including those with normal glucose status at baseline. Mean FPG increased from 98.6 to 125.1 mg/dL (0.6 mg group) and 97.0 to 128.0 mg/dL (0.9 mg group) at month 6. HbA1c rose from 5.8% to 7.2-7.3%. The hyperglycemia mechanism is related to SSTR5-mediated suppression of insulin secretion and incretin hormones (GLP-1, GIP), which was demonstrated in a dedicated mechanism study in healthy volunteers. Patients with HbA1c >8% at baseline are at higher risk for severe hyperglycemia including ketoacidosis. For the LAR formulation in acromegaly, the prevalence of diabetes increased from 30% at baseline to 60% at 12 months in drug-naive patients. Gastrointestinal effects (diarrhea, nausea) typically begin in the first month and resolve without intervention. Cholelithiasis rates of 26-33% across studies necessitate periodic gallbladder ultrasound monitoring. Transient liver enzyme elevations occurred in the first weeks, with 4 cases of concurrent ALT >3x ULN and bilirubin >2x ULN observed across the clinical development program (1 Cushing's patient, 3 healthy volunteers), all resolving upon discontinuation. QT prolongation is dose-dependent with a maximum mean QTcI change of 12.7 ms at therapeutic dose (0.6 mg BID) and 16.6 ms at supra-therapeutic dose (1.95 mg BID), accompanied by dose-dependent bradycardia. Serious adverse events were reported in 25% of patients in the pivotal trial; 17% discontinued due to adverse events. No deaths occurred during the study. The Signifor LAR label added a steatorrhea/malabsorption warning in July 2024.
Clinical check-in
If real-world use or exposure is being considered, review potential interactions, contraindications, and monitoring needs with a licensed clinician rather than relying on summary copy alone.
Sources: [1-10]