USING VIRUSES to kill tumors. “Cancer cells are able to replicate wildly, but there’s a trade-off: They cannot ward off infection as effectively as healthy cells. So scientists have been looking for ways to create viruses that are too weak to damage healthy cells yet strong enough to invade and destroy tumor cells. It has been a long, difficult challenge. . . . Today, several potential cancer-fighting viruses are in trials, including two in Phase 3 trials.”

Faster, please.