Multicenter, single arm, phase II trial on the efficacy of ortataxel in recurrent glioblastoma

Background and purpose: Glioblastoma (GBM) is the most aggressive and frequent subtype of all malignant gliomas. At the time of recurrence, therapeutic options are lacking. Ortataxel, a second-generation taxane was reported to be effective in pre-clinical and phase I clinical studies. The aim of this study was to evaluate a potential therapeutic activity of ortataxel in patients with GBM recurring after surgery and first line treatment. Methods: In this phase II study, according to a two stage design, adult patients with histologically confirmed GBM in recurrence after surgery or biopsy, standard radiotherapy and chemotherapy with temozolomide were considered eligible. Patients included were treated with ortataxel 75 mg/m2 i.v. every 3 weeks until disease progression. The primary objective of the study was to evaluate the activity of ortataxel in terms of progression free survival (PFS) at 6 months after the enrollment. PFS, overall survival at 9 months after the enrollment, objective response rate, compliance and safety were evaluated as secondary endpoints. Results: Between Nov 26, 2013 and Dec 12, 2015, 40 patients were recruited across six centres. The number of patients alive and free from progression at 6 months after the enrollment, observed in the first stage was four (11.4%), out of 35 patients included in the analysis, below the minimum number of events (7 out of 33) required to continue the study with the second stage The most important toxicities were neutropenia and hepatotoxicity that occurred in 13.2% of patients and leukopenia that occurred in 15.8% of patients. Conclusion: Overall ortataxel treatment fail to demonstrate a significant activity in recurrent GBM patients. However in a limited number of patients the drug produced a benefit that lasted for a long time. Trial registration: This study is registered with ClinicalTrials.gov, number NCT01989884