CHICAGO – Taselisib (GDC-0032, RG-7604), the beta-isoform sparing phosphoinositide 3-kinase (PI3K) inhibitor previously advanced to no avail in non-small-cell lung cancer by Roche Holding AG unit Genentech Inc., showed only modest benefit in the phase III SANDPIPER study in individuals with estrogen receptor (ER)-positive, PIK3CA-mutant locally advanced (LA) or metastatic breast cancer (MBC).