The road to effective cancer vaccines has been long and difficult. Although initial attempts to use a vaccine to treat cancer date back to the 1910s, the first effective therapeutic vaccine would not emerge until about a century later, when Sipuleucel-T was used to treat prostate cancer in 2010. While the FDA-approved prostate cancer vaccine generated much excitement, its success has proven difficult to replicate. T-VEC, used to treat metastatic melanoma, is the only other cancer therapeutic vaccine approved by the FDA. While there are some preventative vaccines against viruses…