Primary Objectives:~--To assess the efficacy of SG in patients with R/M salivary gland carcinoma, specifically ACC (cohort 1) and SDC and adeno-NOS (cohort 2)~Secondary Objectives:~To estimate the median duration of response (DOR)~To estimate the median progression-free survival (PFS)~To estimate the median overall survival (OS)~To assess safety of SG~Tertiary / Exploratory Objectives:~--To explore biomarkers that may predict response to therapy
To learn if sacituzumab govitecan can help to control salivary gland cancer.