An objective of the present invention is to provide methods for stabilizing proteins and methods for suppressing protein aggregation, which comprise the step of adding meglumine to the proteins. Another objective of the present invention is to provide agents for suppressing protein aggregation, which comprise meglumine. Still another objective of the present invention is to provide pharmaceutical compositions comprising antibody molecules stabilized by meglumine, methods for producing the pharmaceutical compositions, and kits comprising the pharmaceutical compositions. To achieve the objectives described above, the present inventors assessed the antibody-stabilizing effect of meglumine, an amino sugar. As a result, the inventors discovered that meglumine was useful as a stabilizer for antibody molecules and also as an excipient for freeze-dried preparations.
