A phase II, single arm, open label trial is ongoing to evaluate the efficacy of combination of nivolumab plus talazoparib in unresectable or MM patients harboring a somatic or germline mutation or deletion in BRCA or BRCAness (genes including ARID1A/B/2, ATM, ATR, BAP1, BARD1, BLM, BRCA1/2, BRIP1, CDK4/12, CHEK1/2, DSS1, EMSY, ERCC3, FANCA/D2, HDAC2, IDH1, LIG3/4, MDC1, MLH1/3, MRE11, NBN, PALB2, PRKDC, RAD50/51/54, XRCC6) who have progressed on previous ICI therapy (NCT04187833) [100]. Here, ARID1A is linked to Miyoshi myopathy.