Semax

Semax is a synthetic heptapeptide developed at the Institute of Molecular Genetics of the Russian Academy of Sciences, where it is classified as a nootropic (cognitive-enhancing) and neuroprotective agent. It is a structural analogue of a fragment of the adrenocorticotropic hormone (ACTH), specifically ACTH(4-10), modified with a stabilizing sequence to increase its biological stability.

Its mechanism of action is primarily attributed to its neurotrophic effects on the central nervous system. Semax has been shown in research to rapidly increase the expression of key neurotrophic factors, most notably Brain-Derived Neurotrophic Factor (BDNF) and Nerve Growth Factor (NGF). These proteins are essential for neuronal survival, growth, synaptic plasticity, and cognitive function. Crucially, while derived from ACTH, Semax is specifically designed to be devoid of the hormonal activity of its parent molecule, meaning it does not stimulate the adrenal glands.

Semax is an approved medication in Russia and other Eastern European countries, where it is used for a range of neurological and cognitive conditions, including recovery from stroke and optic nerve atrophy. It is typically administered as a nasal spray to facilitate direct delivery to the brain. However, it is not approved for medical use by the FDA in the United States and remains an experimental compound in Western countries.