Special delivery: bacterial couriers are smuggling drugs into cancers

Engineered bacteria are being developed as living drug-delivery vehicles capable of selectively colonising hypoxic tumour cores and releasing therapeutic payloads on site. The approach could improve the safety and efficacy of chemotherapy, radiotherapy and immunotherapy by concentrating drugs inside tumours while sparing healthy tissue. Nature's feature surveys the current state of the field, including preclinical and early clinical efforts to harness microbial carriers for targeted cancer treatment.