- Participants may have had treatment for no more than 1 prior relapse(NOTE: Relapse is defined as progression following initial therapy (i.e., radiation ± chemotherapy)). The intent therefore is that patients had no more than 2 prior therapies (initial and treatment for 1 relapse). If the participant had a surgical resection for relapsed disease and no antitumor therapy was instituted for up to 12 weeks, and the participant undergoes another surgical resection, this is considered as a second relapse. For participants who had prior therapy for a low-grade glioma, the surgical diagnosis of a high-grade glioma will be considered the first relapse).