There is provided in the present application a pharmaceutical composition comprising a peptide comprising the amino acid sequence of YEKLLDTEI (SEQ ID NO: 1) or a functional variant thereof, a pH adjusting agent, and a filler. The peptide is an active peptide for the treatment of a central nervous system injury. The present application also provides a pharmaceutical composition comprising a chimeric peptide comprising an active peptide and an internalization peptide, a pH adjusting agent, and a filler. The present application also provides medical use of a pharmaceutical composition comprising the active peptide or the chimeric peptide.