HMGCoA reductase inhibitors have a well-known mechanism in controlling cholesterol metabolism. HMGCoA reductase inhibitors also have a less well-known effect on gene expression. This invention provides a new use for HMGCoA reductase inhibitors in the treatment of diseases whose pathogenesis is dependent on neovascularization. HMGCoA reductase inhibitors are administered at anti-angiogenic therapeutic doses for the treatment of primary and metastatic tumors, inflammatory processes involving new vessel formation, diabetic retinopathy, rheumatoid arthritis, and atherosclerosis. HMGCoA reductase inhibitors affect the expression of genes through interference with the function of small GTP binding proteins (such as Rho). Because of the low incidence of side effects with these agents, HMGCoA reductase inhibitors could also be taken prophylactically to prevent the development of diseases in which the pathogenesis is caused by neovascularization.