Table 4.

Biomarkers that predict response to DDR-targeted therapies in combination with ICB

Factor	Agents	Incidence (%)	Validated in clinical trial?	Association with favorable clinical outcome	Predictive versus prognostic	Cancer type	Tissue type for biomarker assessment	Possible assay type for biomarker assessment
Mutational signature 3 reflecting HRD, IS	Niraparib, pembrolizumab	51%	I/II (NCT02657889)	Positive	Prognostic, predictive, or both	Ovarian cancer	Tumor tissue	Targeted gene panel sequencing
Pre-existing CD8+ T-cell infiltrates	Durvalumab, olaparib	NR	II (NCT02484404)	Positive	Predictive	Relapsed SCLC	Tumor tissue	Immunohistochemistry
MDSCs (≤ the median)	Durvalumab, olaparib	NR	I/II (NCT02484404)	Negative	Prognostic	MCRPC	Blood	Multiparametric flow cytometry
CTC	Durvalumab, olaparib	NR	I/II (NCT02484404)	Positive	Prognostic	MCRPC	Blood	Multiparametric flow cytometry
CD83 expression on CD141+ mDCs, > median percentage of Ki67 + PD-1+ cells among total CD8+/CD4+ T cells, > median percentage of Ki67+ HLA-DR CD8+ and CD4+ T cells	Durvalumab, olaparib	NR	I/II (NCT02484404)	Positive	Prognostic	mCRPC	Blood	Multiparametric flow cytometry