PROBLEM TO BE SOLVED: To provide novel applications for a substance by finding the substance that normalizes vascular permeability at an affected site without affecting normal vessels, in a disease associated with vascular malformation, such as solid cancer.SOLUTION: The present invention discloses a drug delivery promoter for promoting the delivery of a drug for the treatment of diseases associated with angiodysplasia to an affected site, the drug delivery promoter containing as an active ingredient a substance that activates lysophosphatidic acid receptors; a pharmaceutical composition for the treatment of diseases associated with angiodysplasia, the pharmaceutical composition containing as an active ingredient a substance that activates lysophosphatidic acid receptors; a vascular normalizing agent containing as an active ingredient the substance that activates a lysophosphatidic acid receptor; and a method for screening drugs for the treatment of diseases associated with angiodysplasia, the method being characterized in that a substance that activates lysophosphatidic acid receptor is selected, the substance being expressed specifically in vascular endothelial cells at the affected site.SELECTED DRAWING: NoneCOPYRIGHT: (C)2020,JPO&INPIT【課題】固形がん等の血管形成異常を伴う疾患において、正常血管に影響を及ぼさず、疾患部位の血管の透過性を正常化させる物質を見出し、当該物質の新規な用途を提供することを課題とする。【解決手段】リゾホスファチジン酸受容体を活性化する物質を有効成分として含有する血管形成異常を伴う疾患の治療薬の疾患部位への送達を促進するための薬剤送達促進剤、リゾホスファチジン酸受容体を活性化する物質を有効成分として含有する血管形成異常を伴う疾患の治療用医薬組成物、リゾホスファチジン酸受容体を活性化する物質を有効成分として含有する血管正常化剤、および疾患部位の血管内皮細胞に特異的に発現しているリゾホスファチジン酸受容体を活性化する物質を選択することを特徴とする血管形成異常を伴う疾患の治療薬のスクリーニング方法。【選択図】なし