Treatment of Recurrent Glioblastoma Multiforme (rGBM) with Antineoplaston AS2-1 in Combination with Targeted Therapy

Treatment of recurrent glioblastoma multiforme (rGBM) poses a difficult challenge. Therefore, the purpose of this report was to evaluate objective response (OR), progression-free survival (PFS), overall survival (OS), and the incidence of adverse events (AEs) in rGBM patients, age 19-70 years, who were treated with antineoplaston AS2-1 (Astugenal) plus targeted therapy. A retrospective analysis was performed. Tumor response was assessed by gadolinium-enhanced magnetic resonance imaging (MRI). Twenty-nine adult rGBM patients were treated between 9/11/2015 and 06/23/2018. Seven had no prior treatment with bevacizumab elsewhere, had radiologic evidence of rGBM, and had MRI assessment of tumor response. The median treatment time was 101 days (range: 55-208 days). OR was seen in six patients (85.7%) with complete disappearance of gadolinium enhancement in four patients (57.1%) and a 50% or greater reduction in gadolinium enhancement in two patients (28.6%). Progressive disease was seen in one patient (14.3%). The median time to first response was 29 days (range: 22-96 days) while the median duration of response was 141 days (range 55-739+ days). Six- and 12-month PFS was 57% and 19%, respectively while 6- and 12-month OS at was 86% and 54%, respectively. Treatment was well-tolerated with no patients experiencing grade 3 or 4 antineoplaston-related toxicity. Regarding response to treatment and toxicity, AS2-1 plus targeted therapy compares favorably with other reported rGBM therapies. Duration of response was shortened by the ill-advised decision of some patients to discontinue treatment after a tumor response was achieved.