Disclosed is a drug composition for angiogenesis therapy that is useful in the treatment or prevention of peripheral arterial diseases; wherein the drug composition is provided with an adeno-associated virus (AAV) that comprises a human prostacyclin synthase (hPGIS) gene responsible for prostaglandin I2 (PGI2), which is a substance having vasodilator action and/or platelet aggregation inhibiting activity, and also comprises a gene that encodes angiogenesis factors. By administering the drug composition to sites that are the objective of therapy, gene introduction into AAV type 1-hPGIS skeletal muscles is achieved, prominent human PGIS gene expression is caused within the skeletal muscle cells, the PGI2 produced and secreted from the muscle cells through the gene expression causes vascular protection activity and angiogenesis-inducing activity, and vascular ischemia is ameliorated.