Research collaborations, especially long-distance and cross-border collaborations, have become increasingly prevalent worldwide . Recent studies highlighted the significant role of research leadership in collaborations . However, existing measures of the research leadership do not take into account the intensity of leadership in the co-authorship network . More importantly, the spatial features, which influence the collaboration patterns and research outcomes, have not been incorporated in measuring the research leadership . To fill the gap, we construct an institution-level weighted co-authorship network that has two types of weight on the edges: the intensity of collaborations and the spatial score (the geographic distance adjusted by the cross-border nature). Based on this network, we propose a novel metric, namely the spatial research leadership rank (SpatialLeaderRank), to identify the leading institutions while considering both the collaboration intensity and the spatial features . Harnessing a dataset of 323,146 journal publications in pharmaceutical sciences during 2010-2018, we perform a comprehensive analysis of the geographical distribution and dynamic patterns of research leadership flows at the institution level . The results demonstrate that the SpatialLeaderRank outperforms baseline metrics in predicting the scholarly impact of institutions . And the result remains robust in the field of Information Science & Library Science.