Current and Investigational Agents Targeting the Phosphoinositide 3‐Kinase Pathway

Prevalent molecular alterations of the phosphoinositide 3‐kinase (PI3K) pathway are found on solid tumors and are expressed in leukocytes, making it a desirable target in both solid and hematologic malignancies. In recent years, two agents targeting this pathway have been approved by the United States Food and Drug Administration, idelalisib and copanlisib, with many others under investigation. Due to the off‐target effects seen with these agents, those under development have varying isoform specificity that mitigates toxicity. In this review, we attempt to illustrate the varying differences among these agents, both mechanistically as well as highlight differences in their respective adverse effect profiles.