Humanized antibody and method for using the same

A non-conjugated humanized antibody capable of binding to mucin subtype 5AC, comprising:

• a heavy chain variable region consisting of
• (1) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 1,
• (2) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 2,
• (3) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 3, or
• (4) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 4;
• and
• a light chain variable region consisting of
• (5) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 5,
• (6) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 6,
• (7) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 7, or
• (8) an amino acid sequence having not less than 95% sequence identity with the amino acid sequence shown in SEQ ID NO:
• 8,
• or an antigen-binding fragment thereof,
• wherein the sequence of the CDR regions of the heavy and light chains are not modified.