Lung cancer vaccines: current status and future prospects

The idea of using a patient’s immune system to attack their cancer is not a new concept. In 1891, William Coley began what is regarded as the first American trial of immunotherapy to treat cancer (1). Coley based his study on observations of a number of patients that developed erysipelas and other bacterial infections and subsequently experienced spontaneous tumor regressions. Coley injected live Streptococcus pyogenes into patients’ tumors with the idea that the body would fight off the infection and as “collateral damage” the tumor would also be destroyed. The first patient that Coley treated developed high fevers, chills and intense headache, consistent with bacterial sepsis. The patient also experienced hemorrhagic necrosis of their tumor leading to tumor shrinkage and a remission. The idea of using live bacteria in a pre-antibiotic era was not ideal and subsequently a number of patients died from sepsis after receiving live bacterial treatments. In response, Coley modified his “vaccination” to use cell-free filtrates of mixed bacterial cultures of Streptococcus and Serratia marcescens (Coley’s toxins) with some reports of responses. The advent of chemotherapy and radiation therapy largely relegated Coley’s work into the history books until the 1970s when Bacillus Calmette-Guerin (BCG) was successfully studied as a treatment for early stage bladder cancer. BCG was approved by the Food and Drug Administration (FDA) in 1990 as a first-line treatment for superficial bladder cancer and remains the treatment of choice for this disease. While BCG immunotherapy has shown efficacy in bladder cancer, it has been largely ineffective in other tumors such as lung cancer (2)