{"entity":{"id":"idea-bio2-engineered-bacteria-payloads","kind":"idea","name":"Engineered bacteria that live in tumours and manufacture drugs there","aka":[],"tldr":"Some harmless bacteria naturally grow in the low-oxygen core of tumours. Engineering them to produce immune-activating drugs turns them into tiny factories inside the tumour.","summary":"Attenuated Salmonella and E. coli Nissle strains colonise hypoxic tumour cores selectively, and synthetic biology allows quorum-controlled payload release of STING agonists, CD47 nanobodies or cytokines. Early human experience with intratumoural bacterial therapy exists, and BCG in bladder cancer is a century-old proof that live bacteria can drive anti-tumour immunity. Safety, biocontainment and manufacturing are the real hurdles.","asOf":"2026-09-08","links":[{"label":"Bottleneck evidence (Cold tumours and the immunosuppressive microenvironment): Haslam & Prasad, Estimation of the percentage of US patients eligible for and responding to checkpoint inhibitors (JAMA Netw Open 2019)","url":"https://doi.org/10.1001/jamanetworkopen.2019.2535"}],"tags":[],"related":[],"cancers":["pancreatic","colorectal"],"sections":[],"technologies":["sting-agonist","bcg-and-intravesical-therapy","cytokine-therapy"],"targets":["cd47"],"drugs":["bcg-intravesical"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":["b-tme-immunosuppression","b-undruggable-targets"],"keyPapers":["paper-haslam-jama-netw-open","paper-cd47-pancreatic-pharmacol-res-2022","paper-cd47-colorectal-cancers-basel-2025","paper-cd47-colorectal-cancer-res-commun-2025"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"A quorum-regulated engineered strain colonises human tumours at detectable levels after intravenous or intratumoural dosing and produces measurable local payload and immune activation without bacteraemia above grade 2.","rationale":"Tumour hypoxia is a selectivity handle that no small molecule can match, and payload release can be genetically gated to bacterial density inside the lesion. Escalating dose is a colonisation problem rather than a plasma exposure problem.","test":"First-in-human intratumoural dosing in accessible lesions with quantitative colonisation, payload and safety endpoints, plus a documented kill-switch demonstration.","maturity":"preclinical-evidence","actor":"industry","cost":"medium","horizonYears":9},"route":"/ideas/idea-bio2-engineered-bacteria-payloads/","neighbours":{"cancer":[{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"pancreatic","kind":"cancer","name":"Pancreatic ductal adenocarcinoma","route":"/cancers/pancreatic/"}],"technology":[{"id":"cytokine-therapy","kind":"technology","name":"Cytokines & engineered cytokines","route":"/technologies/cytokine-therapy/"},{"id":"bcg-and-intravesical-therapy","kind":"technology","name":"Intravesical therapy (BCG, chemotherapy, devices, gene and viral therapy)","route":"/technologies/bcg-and-intravesical-therapy/"},{"id":"sting-agonist","kind":"technology","name":"STING & innate immune agonists","route":"/technologies/sting-agonist/"}],"target":[{"id":"cd47","kind":"target","name":"CD47","route":"/targets/cd47/"}],"drug":[{"id":"bcg-intravesical","kind":"drug","name":"Intravesical BCG","route":"/drugs/bcg-intravesical/"}],"bottleneck":[{"id":"b-tme-immunosuppression","kind":"bottleneck","name":"Cold tumours and the immunosuppressive microenvironment","route":"/bottlenecks/b-tme-immunosuppression/"},{"id":"b-undruggable-targets","kind":"bottleneck","name":"The undruggable drivers","route":"/bottlenecks/b-undruggable-targets/"}],"paper":[{"id":"paper-haslam-jama-netw-open","kind":"paper","name":"Estimation of the Percentage of US Patients With Cancer Who Are Eligible for and Respond to Checkpoint Inhibitor Immunotherapy Drugs","route":"/key-papers/paper-haslam-jama-netw-open/"},{"id":"paper-cd47-colorectal-cancers-basel-2025","kind":"paper","name":"Expression and Clinical Significance of CD47 in Colorectal Cancer: A Review","route":"/key-papers/paper-cd47-colorectal-cancers-basel-2025/"},{"id":"paper-cd47-pancreatic-pharmacol-res-2022","kind":"paper","name":"Overcoming immunotherapeutic resistance in PDAC: SIRPα-CD47 blockade","route":"/key-papers/paper-cd47-pancreatic-pharmacol-res-2022/"},{"id":"paper-cd47-colorectal-cancer-res-commun-2025","kind":"paper","name":"Phase II Clinical Trial and Preclinical Evaluation of a Novel CD47 Blockade Combination in Refractory Microsatellite-Stable Metastatic Colorectal Cancer","route":"/key-papers/paper-cd47-colorectal-cancer-res-commun-2025/"}]}}