{"entity":{"id":"idea-bio2-intracavitary-immunotherapy","kind":"idea","name":"Treat the body cavity, not the bloodstream, for surface spread","aka":[],"tldr":"Intracavitary immunotherapy targets cancer that coats the lining of the abdomen or chest, which drugs given by drip barely reach. Delivering it straight into the cavity gives far higher local doses.","summary":"Peritoneal and pleural surface disease has poor drug penetration from the circulation, which is why intraperitoneal chemotherapy and pressurised aerosol delivery persist despite mixed evidence. Regional immunotherapy (intraperitoneal interleukin-2, checkpoint antibodies, T-cell engagers or CAR-T cells) reaches high local concentrations, and intrapleural mesothelin CAR-T has shown feasibility. The unresolved questions are dosing, drainage-related loss and cytokine toxicity.","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":["idea-mesothelin-car-t-regional"],"cancers":["ovarian","gastric","mesothelioma"],"sections":[],"technologies":["hipec","car-t","t-cell-engager","checkpoint-inhibitor"],"targets":["mesothelin"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["peritoneal-metastasis"],"trials":[],"people":[],"bottlenecks":["b-tme-immunosuppression","b-metastasis-biology"],"keyPapers":["paper-haslam-jama-netw-open","paper-mesothelin-mesothelioma-cancer-discov-2016","paper-mesothelin-mesothelioma-clin-cancer-res-2004","paper-mesothelin-mesothelioma-j-clin-oncol-2016"],"journals":[],"dependsOn":[],"notes":[],"hypothesis":"Intracavitary administration achieves at least tenfold higher local drug exposure than intravenous dosing at equal systemic exposure, and produces higher rates of cytological clearance of malignant effusion.","rationale":"Pharmacology strongly favours regional delivery for a compartmentalised disease, and cytological clearance provides a fast, objective, inexpensive endpoint. Regional cell therapy has already been shown to be safer than systemic in the pleural space.","test":"A pharmacokinetic and pharmacodynamic study comparing intracavitary with intravenous dosing of the same agent, with cytological clearance and paired compartment sampling as endpoints.","maturity":"early-clinical","actor":"clinic","cost":"medium","horizonYears":6},"route":"/ideas/idea-bio2-intracavitary-immunotherapy/","neighbours":{"idea":[{"id":"idea-mesothelin-car-t-regional","kind":"idea","name":"Regionally delivered mesothelin CAR-T with PD-1 blockade","route":"/ideas/idea-mesothelin-car-t-regional/"}],"cancer":[{"id":"gastric","kind":"cancer","name":"Gastric & gastro-oesophageal junction cancer","route":"/cancers/gastric/"},{"id":"mesothelioma","kind":"cancer","name":"Mesothelioma","route":"/cancers/mesothelioma/"},{"id":"ovarian","kind":"cancer","name":"Ovarian cancer","route":"/cancers/ovarian/"}],"technology":[{"id":"car-t","kind":"technology","name":"CAR-T cell therapy","route":"/technologies/car-t/"},{"id":"hipec","kind":"technology","name":"HIPEC / PIPAC (intraperitoneal chemotherapy)","route":"/technologies/hipec/"},{"id":"checkpoint-inhibitor","kind":"technology","name":"Immune checkpoint inhibitors","route":"/technologies/checkpoint-inhibitor/"},{"id":"t-cell-engager","kind":"technology","name":"T-cell engagers (bispecific)","route":"/technologies/t-cell-engager/"}],"target":[{"id":"mesothelin","kind":"target","name":"Mesothelin","route":"/targets/mesothelin/"}],"term":[{"id":"peritoneal-metastasis","kind":"term","name":"Peritoneal metastasis","route":"/terms/peritoneal-metastasis/"}],"bottleneck":[{"id":"b-tme-immunosuppression","kind":"bottleneck","name":"Cold tumours and the immunosuppressive microenvironment","route":"/bottlenecks/b-tme-immunosuppression/"},{"id":"b-metastasis-biology","kind":"bottleneck","name":"Metastasis is understood least and studied last","route":"/bottlenecks/b-metastasis-biology/"}],"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-mesothelin-mesothelioma-j-clin-oncol-2016","kind":"paper","name":"Mesothelin Immunotherapy for Cancer: Ready for Prime Time?","route":"/key-papers/paper-mesothelin-mesothelioma-j-clin-oncol-2016/"},{"id":"paper-mesothelin-mesothelioma-cancer-discov-2016","kind":"paper","name":"Mesothelin-Targeted CARs: Driving T Cells to Solid Tumors","route":"/key-papers/paper-mesothelin-mesothelioma-cancer-discov-2016/"},{"id":"paper-mesothelin-mesothelioma-clin-cancer-res-2004","kind":"paper","name":"Mesothelin: a new target for immunotherapy","route":"/key-papers/paper-mesothelin-mesothelioma-clin-cancer-res-2004/"}]}}