A new immunotherapy drug has demonstrated early promise in a recent prostate cancer clinical trial . The drug, called VIR-5500, is a "masked T-cell engager". This type of immunotherapy ignites our own immune arsenal to fight cancer. In the trial, which is still in progress and has not yet undergone peer review , patients with advanced prostate cancer who had failed to respond to other treatments were given VIR-5500. Remarkably, initial findings showed that in the patients who received the