(D-His(Bzl)6)-LHRH (1-7) free acid is a synthetic peptide derived from luteinizing hormone-releasing hormone (LHRH). It achieves enhanced stability and biological activity through the introduction of non-natural amino acid residues at specific positions within the LHRH molecule. This modification extends the drug's half-life in the body, reduces its rate of rapid metabolism and clearance, and subsequently increases its efficacy in inhibiting cell proliferation.