Provided are a pharmaceutical composition and the like for use in treating or preventing angiogenic diseases. A combination of a monoclonal antibody or antigen-binding fragment thereof having features (i) to (v) below and a VEGF antagonist； or a pharmaceutical composition comprising the antibody or antigen-binding fragment thereof and a VEGF antagonist:(i) binding to ROBO4 protein with a Kd value of 1 × 10-8 M or less；(ii) specifically binding to human ROBO4 protein shown in SEQ ID NO: 2 in the sequence listing；(iii) suppressing or inhibiting migration of vascular endothelial cells in vitro in the absence of a crosslinking antibody；(iv) suppressing or inhibiting angiogenesis in vivo； or(v) being a chimeric antibody or a humanized antibody.
