The sodium salt form of silmitasertib, an orally bioavailable small-molecule inhibitor of the enzyme casein kinase II (CK2), with potential antineoplastic, anti-viral and immunomodulatory activities. Upon oral administration, silmitasertib selectively binds to and inhibits the activity of CK2. This may inhibit proliferation of CK2-expressing tumor cells, and may also inhibit the replication of severe acute respiratory syndrome coronavirus-2 (SARS-COV-2). In addition, this may restore normal host cell cytokine regulation, prevent cytokine storm and suppress the hyperactivation of the innate immune system. CK2, a protein kinase often overexpressed in a variety of cancer cell types, appears to be correlated with malignant transformation, tumor growth and survival. CK2 regulates a diverse array of pro-survival cellular processes including epidermal growth factor receptor (EGFR) signaling, PI3K/AKT/mTOR signaling, hedgehog (Hh) signaling, Hsp90 machinery, hypoxia, and interleukin (IL)-6 expression. CK2 also regulates the activity of XRCC1 and MDC1, two mediator/adaptor proteins that are essential for DNA repair. CK2 is upregulated by SARS-COV-2 and is associated with SARS-COV-2 viral replication and the development of cytokine storm.