{"entity":{"id":"idea-bio2-antibiotic-stewardship-io","kind":"idea","name":"Protect the gut flora of patients about to start immunotherapy","aka":[],"tldr":"Antibiotics given in the weeks before immunotherapy are linked to much worse results. A simple stewardship rule could preserve benefit at no cost.","summary":"Multiple cohort studies and meta-analyses report substantially worse survival in patients receiving broad-spectrum antibiotics within roughly 30 days before checkpoint blockade. Causality is uncertain because antibiotic use marks infection and frailty. A stewardship intervention (narrow-spectrum choice, shortest effective duration, deferral of non-urgent prophylaxis, and where necessary delaying checkpoint start) is testable and cheap either way.","asOf":"2026-09-08","links":[{"label":"Bottleneck evidence (No one can predict who responds to immunotherapy): Haslam & Prasad (JAMA Network Open 2019)","url":"https://doi.org/10.1001/jamanetworkopen.2019.2535"}],"tags":[],"related":[],"cancers":["nsclc","melanoma","rcc"],"sections":[],"technologies":["checkpoint-inhibitor"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":["laurence-zitvogel"],"bottlenecks":["b-immunotherapy-response","b-care-fragmentation","b-generic-repurposing"],"keyPapers":["paper-haslam-jama-netw-open"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"A protocolised antibiotic stewardship bundle before checkpoint therapy improves 12-month survival compared with usual prescribing, which would establish that at least part of the observed association is causal and modifiable.","rationale":"The association is large and consistent across tumour types, and antibiotic prescribing is highly modifiable. If the effect is confounding rather than causation, the trial establishes that cheaply and stops a growing body of over-interpretation.","test":"A cluster-randomised stewardship trial across oncology units, with antibiotic exposure metrics as process outcomes and survival as the clinical endpoint, plus a microbiome substudy.","maturity":"early-clinical","actor":"clinic","cost":"small","horizonYears":3},"route":"/ideas/idea-bio2-antibiotic-stewardship-io/","neighbours":{"cancer":[{"id":"melanoma","kind":"cancer","name":"Melanoma","route":"/cancers/melanoma/"},{"id":"nsclc","kind":"cancer","name":"Non-small-cell lung cancer","route":"/cancers/nsclc/"},{"id":"rcc","kind":"cancer","name":"Renal cell carcinoma","route":"/cancers/rcc/"}],"technology":[{"id":"checkpoint-inhibitor","kind":"technology","name":"Immune checkpoint inhibitors","route":"/technologies/checkpoint-inhibitor/"},{"id":"probiotics-antibiotic-stewardship-io","kind":"technology","name":"Probiotics, antibiotics and stewardship around immunotherapy","route":"/technologies/probiotics-antibiotic-stewardship-io/"}],"person":[{"id":"laurence-zitvogel","kind":"person","name":"Laurence Zitvogel","route":"/people/laurence-zitvogel/"}],"bottleneck":[{"id":"b-care-fragmentation","kind":"bottleneck","name":"Fragmented care and guideline gaps","route":"/bottlenecks/b-care-fragmentation/"},{"id":"b-generic-repurposing","kind":"bottleneck","name":"No incentive to repurpose cheap drugs","route":"/bottlenecks/b-generic-repurposing/"},{"id":"b-immunotherapy-response","kind":"bottleneck","name":"No one can predict who responds to immunotherapy","route":"/bottlenecks/b-immunotherapy-response/"}],"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/"}],"idea":[{"id":"idea-nl-diet-covariates-io-trials","kind":"idea","name":"Capture diet, fibre and antibiotic exposure in every immunotherapy pivotal trial","route":"/ideas/idea-nl-diet-covariates-io-trials/"}]}}