Abstract
Capiversatib is a pan-Ak strain transforming inhibitor used in combination with fulvestrant for the treatment of hormone receptor-positive advanced breast cancer and has a known adverse effect of hyperglycemia. We present 3 cases of severe hyperglycemia, 2 of which presented as diabetic ketoacidosis, in patients being treated with capivasertib. These cases demonstrate the severity of hyperglycemia that can result from capivasertib use, as well as highlight treatment regimens and patient outcomes.