idelalisib + ofatumumab

**Idelalisib + ofatumumab** is an investigational combination therapy comprised of idelalisib, a small molecule phosphatidylinositol 3-kinase delta (PI3Kδ) inhibitor, and ofatumumab, a fully human monoclonal antibody targeting CD20 on B lymphocytes. This combination has been primarily evaluated in patients with relapsed or refractory chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). Idelalisib induces apoptosis and inhibits cell signaling involved in B-cell survival and trafficking, while ofatumumab mediates direct B-cell lysis primarily through complement-dependent and antibody-dependent cytotoxicity. The combination has demonstrated improved progression-free survival and objective response rates compared to ofatumumab alone in clinical trials for relapsed CLL.