Semax (CAS 80714-61-0), also known as ACTH(4-7)-PGP, is a synthetic heptapeptide analogue of a fragment of adrenocorticotropic hormone (ACTH). With the molecular formula C37H51N9O10S and a molecular weight of 813.93 g/mol, Semax is defined by the amino acid sequence Met-Glu-His-Phe-Pro-Gly-Pro, consisting of the ACTH(4-7) tetrapeptide core extended at the C-terminus with a Pro-Gly-Pro tripeptide motif. This structural modification is considered relevant to its metabolic stability and central nervous system accessibility. Produced via solid-phase peptide synthesis, ACTH(4-7)-PGP is associated with neurotrophic factor signalling pathways in preclinical neuroscience research.

Semax has been extensively investigated in preclinical neurobiology as one of the most frequently referenced synthetic melanocortin-derived peptides. The ACTH(4-10) fragment from which it is derived has been the subject of extensive structure-activity research examining the non-endocrine signalling properties of melanocortin peptides independently of their adrenal axis activity. In vitro studies have investigated Semax’s interaction with brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) expression, with published research documenting ACTH(4-7)-PGP-mediated activation of BDNF and NGF in rat basal forebrain tissue preparations and characterising the neurotrophic factor response as a basis of Semax’s neurotrophic signalling profile [1]. In vivo rodent studies have examined ACTH(4-7)-PGP in experimental models of cerebral ischaemia, with published research documenting Semax’s influence on nitric oxide levels in ischaemic rat brain and characterising neuroprotective effects through NO-mediated signalling under conditions of reduced cerebral perfusion [2], making Semax a key reference compound in melanocortin-derived neuropeptide research across neurotrophic factor signalling and neuroprotection models.

Semax is manufactured in a cGMP compliant laboratory to a guaranteed purity of 98% or above. Every batch is independently tested using HPLC and MS-UPLC analysis before dispatch. Vials are vacuum sealed and stored in a temperature controlled, monitored cold storage system. Certificates of Analysis are available on request.

Sold strictly for in vitro research purposes only. Not for human consumption. Intended for use by qualified researchers in laboratory settings only.

Editorial Team

Dr. Martina Rossi, PhD

Scientific Contributor and Reviewer

Reviewed and approved 14 June 2026

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