Semax is a synthetic peptide developed from a portion of ACTH, a naturally occurring hormone involved in the body's response to stress. Semax was designed to investigate certain biological effects associated with this hormone without reproducing all of its hormonal activity. It has attracted scientific interest for its potential influence on brain function, learning, memory, and the processes that help nerve cells respond to stress or injury.

Research has explored how Semax may influence communication between nerve cells, attention, memory, and the brain's natural protective processes. Some laboratory studies have examined its relationship with proteins that support the growth and maintenance of nerve cells. These proteins help brain cells remain healthy and maintain connections, which are important for learning and normal cognitive function.

Semax has been investigated through laboratory studies, animal research, and human studies conducted primarily in Russia. Research has included neurological conditions and experimental models of brain injury, alongside investigations of attention and cognitive performance. Some studies have reported encouraging findings, although the quality, accessibility, and independent replication of the evidence vary considerably.

Despite its history of scientific investigation, Semax does not have the extensive international clinical evidence available for widely established neurological treatments. Many proposed effects remain supported primarily by preclinical findings or smaller regional studies. Larger, independently conducted human trials are needed to clarify its effects, safety, and potential clinical significance.