The forecast shows 2018’s gonna make it rain targeted-therapies, but we’ve got you covered on all the latest. As a reminder, phosphoinositide 3-kinases (PI3K) are key proteins across a whole host of cell-signaling pathways. In general, this makes PI3K less than an ideal target for drug therapy. The isomer PI3K-delta is pretty specific to heme cells, though, and idelalisib (the first in class PI3K-delta inhibitor) quickly became all the rage for the treatment of chronic lymphocytic leukemia back in 2014. Unfortunately, the effects of idelalisib weren’t as specific as initially hoped, and grade 5 autoimmune-related colitis has majorly dampened the excitement surrounding its rollout. Now there is a next-generation PI3K-delta inhibitor making waves. It goes by the name of umbralisib, and phase 1 results indicate it has promising safety and efficacy in refractory heme malignancies. TBL: PI3K-delta inhibitors are back.