This article appeared in the July/August 2021 issue of Discover magazine as "When Viruses Heal." Subscribe for more stories like these.
Sitting in an isolated room at Beth Israel Deaconess Medical Center in Boston, Frank Nielsen steeled himself for the first injection. Doctors were about to take a needle filled with herpes simplex virus, the strain responsible for cold sores, and plunge it directly into his scalp. If all went well, it would likely save his life.
Nielsen was a cancer survivor and, once again, a cancer patient. His melanoma, which had responded to conventional treatments the first time around, had returned with a frightening aggressiveness. Within weeks, a lump on his scalp had swelled into an ugly mass. Unlike the first time, options like surgery weren’t viable — it was growing too quickly.
As a last resort, his doctors turned to a cutting-edge drug known as T-VEC, approved in 2015 in the U.S. But the treatment, part of a promising field of cancer care known as immunotherapy, doesn’t sound much like a drug at all. T-VEC consists of a genetically modified virus that acts as both soldier and scout within the body, attacking tumor cells directly and calling in reinforcements from the immune system. Nielsen’s doctors hoped it would team up with the immunotherapy drug Keytruda, which enables the immune system to recognize and destroy tumor cells, to bring his cancer under control.
