** Shares of cancer treatment firm Nuvation Bio NUVB.N rise 5.3% to $6.11

** Co says its experimental brain cancer drug, safusidenib, showed a 52% confirmed response rate in patients with IDH1-mutant glioma, a common type of brain tumor caused by a gene mutation

** Says nearly 80% of patients were alive without their disease worsening three years after starting treatment in a Japanese mid-stage study

** Co will start a late-stage study outside the U.S. in about 140 newly diagnosed patients who have not received chemotherapy or radiation

** Says safusidenib's safety profile remained manageable

** Including session's move, stock down ~32% YTD