PIK3CA and Hyperglycemia: Unfortunately, many patients treated with alpelisib develop hyperglycemia (in SOLAR-1 trial 63.7% of any grade and 36.6% of Grade 3 or 4) frequently leading to dose reductions, treatment delays, and/or discontinuation.8 Hyperglycemia is a reversible, on-target effect of phosphatidylinositol 3-kinase (PI3K) inhibition.