Abstract: A method for nasal administration of a pharmaceutical composition comprising a hydrophilic bioactive substance and any one of (a) to (c): (a) a peptide having the amino acid sequence shown in SEQ ID NO:1; (b) a peptide having the same amino acid sequence as shown in SEQ ID NO:1 except that one or several amino acids are deleted, substituted and/or added, the peptide having nasal mucosal permeability; (c) a peptide having an amino acid sequence represented by the reverse sequence of (a) or (b), the peptide having nasal mucosal permeability, with the proviso that a C-terminal amidated peptide is excluded. A hydrophilic bioactive substance having a low transmucosal absorption capability which has conventionally been able to be administered by only injection can be nasally administered. Such a pharmaceutical composition is useful for improvement of the pain and the inconvenience of patients caused by administration by injection.

Abstract: A cell-penetrating peptide of (A) to (D) below gives cell membrane permeability and transmucosal absorbability to a physiologically active substance: (A) a peptide having the amino acid sequence of SEQ ID NO:1; (B) a peptide represented by SEQ ID NO:1 except that one or several basic amino acids are changed; (C) a peptide represented by SEQ ID NO:1 except that 1 to 5 amino acids are changed; (D) a peptide having: the reverse sequence of any of (A) to (C); an amino acid sequence which is the same as the reverse sequence of (A) except that one or several basic amino acids are changed; or an amino acid sequence which is the same as the reverse sequence of (A) except that 1 to 5 amino acids are changed.

Abstract: A cell-penetrating peptide of (A) to (D) below gives cell membrane permeability and transmucosal absorbability to a physiologically active substance: (A) a peptide having the amino acid sequence of SEQ ID NO:1; (B) a peptide represented by SEQ ID NO:1 except that one or several basic amino acids are changed; (C) a peptide represented by SEQ ID NO:1 except that 1 to 5 amino acids are changed; (D) a peptide having: the reverse sequence of any of (A) to (C); an amino acid sequence which is the same as the reverse sequence of (A) except that one or several basic amino acids are changed; or an amino acid sequence which is the same as the reverse sequence of (A) except that 1 to 5 amino acids are changed.

Abstract: By a pharmaceutical composition for nasal administration comprising a hydrophilic bioactive substance and any one of (a) to (c) below, with the proviso that a C-terminal amidated peptide is excluded, a hydrophilic bioactive substance having a low transmucosal absorption capability which has conventionally been able to be administered by only injection can be nasally administered. Such a pharmaceutical composition is useful for improvement of the pain and the inconvenience of patients caused by administration by injection. (a) A peptide having the amino acid sequence shown in SEQ ID NO:1. (b) A peptide having the same amino acid sequence as shown in SEQ ID NO:1 except that one or several amino acids are deleted, substituted and/or added, the peptide having nasal mucosal permeability. (c) A peptide having an amino acid sequence represented by the reverse sequence of (a) or (b), the peptide having nasal mucosal permeability.