Dipyridamole is a drug used to treat coronary and peripheral artery disease. It reduces clots and dilates blood vessels. A study published by Rhodes, et al. in Lancet, March 23, 1985 demonstrated that melanoma patients given 300mg of Dipyridamole a day had a 5 year survival of 77%, versus an expected survival of 32% in patients not treated with Dipyridamole. One initial thought was that since this drug reduces platelet aggregation, it might decrease the ability of cancer cells to spread in the blood and adhere to other locations, creating metastasis. In a study published by Spano, et al. in Clinical & Experimental Metastasis, January 2013, titled “Dipyridamole Prevents Triple-negative Breast-cancer Progression,” they demonstrate in the mouse model that Dipyridamole decreased the primary tumor by 67.5% and metastasis formation by 47.5%. In their study, they discovered that Dipyridamole produced a significant decrease in tumor- associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs), both which boost the anti-cancer immune response. Dipyridamole also results in a decrease in adenosine, which is a metabolic suppressor of the immune system. As this study shows, basically, there are several mechanisms in which Dipyridamole may help enhance the immune response.