{"entity":{"id":"b7-h3-expression","kind":"biomarker","name":"B7-H3 (CD276) expression","aka":["B7-H3","CD276 expression","B7-H3 positive"],"tldr":"B7-H3 is an immune checkpoint protein overexpressed on small-cell lung, prostate and many solid tumours. Ifinatamab deruxtecan is in phase 3 for small-cell lung cancer without an expression cut-off; nothing is approved.","summary":"Ifinatamab deruxtecan (I-DXd) is being compared with topotecan or other chemotherapy in relapsed small-cell lung cancer in IDeate-Lung02 (NCT06203210) with no B7-H3 selection; earlier phase studies found responses across expression levels. Other B7-H3 ADCs and radioligands are in early trials. No regulator has approved a B7-H3-directed drug.","asOf":"2026-09-23","links":[{"label":"ClinicalTrials.gov NCT06203210 (IDeate-Lung02)","url":"https://clinicaltrials.gov/study/NCT06203210"}],"tags":["biomarker","surface-antigen","no-threshold"],"related":["dll3-expression"],"cancers":["sclc","extensive-stage-sclc","prostate-mcrpc"],"sections":[],"technologies":[],"targets":[],"drugs":["ifinatamab-deruxtecan"],"companies":[],"institutions":[],"pathways":[],"terms":[],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"target":"b7h3","measurement":"ihc-score","scoringRule":{"text":"The label names the antigen in the drug's description but does not require it to be measured before treatment; no approval threshold exists for this readout.","quote":"IDeate-Lung02: ifinatamab deruxtecan versus treatment of physician's choice in relapsed small cell lung cancer","source":"https://clinicaltrials.gov/study/NCT06203210","sourceLabel":"ClinicalTrials.gov NCT06203210 (IDeate-Lung02)"},"thresholds":[],"definedBy":{"label":"IDeate-Lung02 (NCT06203210)","url":"https://clinicaltrials.gov/study/NCT06203210"},"tests":[],"assays":[],"companionDiagnostics":[],"forPatient":"B7-H3 is a research target. If you have small-cell lung cancer that has returned, a trial of ifinatamab deruxtecan may be open to you without any B7-H3 test; ask your team."},"route":"/biomarkers/b7-h3-expression/","neighbours":{"biomarker":[{"id":"dll3-expression","kind":"biomarker","name":"DLL3 expression","route":"/biomarkers/dll3-expression/"}],"cancer":[{"id":"extensive-stage-sclc","kind":"cancer","name":"Extensive-stage small-cell lung cancer","route":"/cancers/extensive-stage-sclc/"},{"id":"prostate-mcrpc","kind":"cancer","name":"Metastatic castration-resistant prostate cancer","route":"/cancers/prostate-mcrpc/"},{"id":"sclc","kind":"cancer","name":"Small-cell lung cancer","route":"/cancers/sclc/"}],"drug":[{"id":"ifinatamab-deruxtecan","kind":"drug","name":"Ifinatamab deruxtecan","route":"/drugs/ifinatamab-deruxtecan/"}],"target":[{"id":"b7h3","kind":"target","name":"B7-H3","route":"/targets/b7h3/"}]}}