An FDA expert panel voted 16-0, with one abstention, recommending that future FDA approvals of PI3K inhibitors be supported by randomized data. The four currently-approved PI3K inhibitors for treating hematologic malignancies received FDA approval based on single-arm data. Although these drugs have offered durable ORR and improvements in PFS, randomized data presented at the hearing showed they are associated with higher rates of serious adverse events, including fatality.