tetracosactide acetate: clinical use

Prescribing considerations

• Confirm allergy and asthma history, including previous reactions to ACTH or tetracosactide.
• Administer only under medical supervision with facilities and treatment available for anaphylaxis.
• Therapeutic effects reflect increased endogenous adrenal steroids; use particular care with hypertension, diabetes, renal impairment, osteoporosis, thromboembolic risk, myasthenia gravis and relevant gastrointestinal disease.
• Altered cortisol-binding globulin in pregnancy, oestrogen use, critical illness, severe liver disease, nephrotic syndrome or postoperative states can distort total cortisol results; consider appropriate alternative measures.

Contraindications and cautions

• Hypersensitivity to tetracosactide, ACTH or an excipient.
• Known asthma or other allergic disorder for this depot product.
• Acute psychosis, infectious disease, Cushing’s syndrome, peptic ulcer or refractory heart failure.
• Treatment of primary adrenocortical insufficiency or adrenogenital syndrome.
• Intravenous administration of the depot suspension.

Monitoring

• Observe for immediate local or systemic hypersensitivity after injection.
• During therapeutic use, consider blood pressure, glucose, electrolytes, fluid status, infection, psychiatric symptoms and ocular, bone and muscle effects.
• For prolonged paediatric treatment, monitor growth; the SmPC also advises cardiac assessment in young children because reversible myocardial hypertrophy has rarely occurred.
• Interpret adrenal testing in the clinical context and account for medicines or conditions affecting cortisol-binding globulin.

Clinical pharmacology

Tetracosactide contains the first 24 amino acids of natural ACTH. Receptor activation in the adrenal cortex stimulates cyclic AMP and corticosteroid synthesis. In the depot formulation, adsorption onto zinc phosphate provides sustained release from the intramuscular injection site.

Formulation and product differences

• The selected depot product is a milky suspension of tetracosactide adsorbed onto zinc phosphate.
• It settles on standing and must be shaken before use.
• It is for intramuscular administration only and must not be given intravenously.
• It should be protected from light and refrigerated.