In the bad old days of cancer treatment, it was the nasty side effects of chemotherapy that often ended up limiting treatment – and while checkpoint inhibitors have raised the bar in terms of efficacy and safety, they can have dangerous and unpleasant off-target consequences, too. Finding ways to focus the immune system on cancer and limiting any off-target effects will not only make checkpoint inhibitor therapy more tolerable but could also improve survival rates – and Sweden’s Ilya Pharma AB aims to do this with a novel approach combining synthetic biology with cell therapy.