Today, immune checkpoint inhibitors — a type of immunotherapy — have been approved for more than 25 types of cancer. For advanced melanoma, in particular, outcomes have been astounding. Just 15 years ago, only 1 in 20 patients with metastatic skin cancer would survive for five years. Today, advanced melanoma patients treated with a combination of immunotherapies have a 10-year survival rate of 50 percent or higher.

These advances build on decades of research across multiple institutions and continue as researchers work to refine these therapies by targeting the unique features of each patient’s tumor and immune system and engineering smarter immune cells that can adapt and persist in the body. This is just one example of the building-block process of work in labs that has over the years led to breakthroughs in therapies and treatment.

The modern era of cancer immunotherapy can be traced to 1891, when American surgeon William B. Coley injected bacteria into patients with inoperable cancers, sometimes causing their tumors to shrink. Yet, without a clear understanding of how and why this approach worked — and in an era before antibiotics, when the risk of deadly infection was high — physicians continued to favor surgery and radiotherapy over immunotherapy well into the 1900s.

Today, Coley is recognized as the “father of cancer immunotherapy” for his pioneering efforts. But his legacy might have faded into obscurity were it not for major federal investments in U.S. biomedical research after World War II. It was this influx of funding for basic science in the latter half of the 20th century that enabled scientists to begin realizing the long-elusive promise of using the immune system to fight cancer.

Life-saving care, decades in the making