NA Semax (N-Acetyl Semax) is an acetylated form of Semax, a synthetic heptapeptide derived from the ACTH(4-7) sequence with a Pro-Gly-Pro C-terminal extension for improved stability. The N-acetyl modification further enhances metabolic resistance and is generally considered to increase potency. Semax is studied for its ability to upregulate BDNF (brain-derived neurotrophic factor) and NGF in the brain, supporting neuroplasticity and neuroprotection. Research has examined its effects on cognitive function, attention, memory consolidation, and recovery from neurological injury. It is one of the most studied peptide nootropics in the research literature.