“That’s why expert opinion ends up being very important here,” said Expert Panel Co-Chair Angela DeMichele, MD, MSCE, FASCO, of Penn Medicine. “We don’t have data on optimal sequencing in the first, second, and third line, and we don’t have data on head-to-head comparison for drugs that are targeting PIK3CA pathway alterations. That’s where an expert guideline comes in—when you don’t have that kind of feedback.”