Alsactide (INN) (brand name Synchrodyn 1-17 or simply Synchrodyn, former development code name Hoechst 433), also known as alisactide, is a synthetic peptide and analogue of adrenocorticotropic hormone (ACTH) which is used in Italy as a diagnostic agent in kidney function for adrenal insufficiency.

[1][2][3] Like ACTH, alsactide is thought to act as a non-selective agonist of the melanocortin receptors, including the ACTH receptor (MC2R).

[1][citation needed] However, it appears to show a different profile of receptor selectivity relative to ACTH, as it apparently demonstrated no evidence of inhibition of endogenous ACTH in Addison's disease patients.

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