Semax is a synthetic peptide analog of a fragment of adrenocorticotropic hormone (ACTH). Specifically, it is a heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Developed as a neuroactive compound, Semax lacks the hormonal activity of ACTH. In laboratory research settings, it is extensively investigated for its potential effects on the central nervous system, including its influence on neurotransmitter levels, neurotrophic factor expression, and cerebral circulation.

Scientific literature explores the role of Semax in modulating the synthesis of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF). It is frequently utilized in studies examining cognitive function, neuroprotection following ischemic events, and the physiological mechanisms underlying attention and memory formation in controlled, non-human experimental models.