Buparlisib has demonstrated an ability to cross the blood–brain barrier and inhibit the PI3K pathway in the brain, and has shown synergy with temozolomide and docetaxel in murine xenografts of PTEN-null GBM.6 A phase I trial is investigating buparlisib in combination with adjuvant temozolomide and with concomitant radiotherapy and temozolomide in newly diagnosed GBM (NCT01473901). The gene discussed is PTEN; the disease is glioblastoma.