Phase I-II trial of imatinib mesylate (Gleevec; STI571) in treatment of recurrent oligodendroglioma and mixed oligoastrocytoma. North central cancer treatment group study N0272 (ALLIANCE/NCCTG)

Purpose: To evaluate the pharmacokinetics and efficacy of imatinib in patients with recurrent oligodendroglial tumors. Methods: Patients with progressive WHO grade II-III recurrent tumors after prior RT and chemotherapy were eligible. A phase I dose-escalation study was conducted for patients on enzyme-inducing anticonvulsants (EIAC). A phase II study for non-EIAC patients utilized a fixed dose of 600 mg/D. Primary efficacy endpoint was 6-month progression-free survival (PFS6). A 2-stage design was utilized, with 90% power to detect PFS6 increase from 25 to 45%. Results: In the Phase I, maximum tolerated dose was not reached at 1200 mg/D. For phase II patients, overall PFS6 was 33% and median PFS 4.0 months (95% CI 2.1, 5.7). Median overall survival (OS) was longer in imatinib-treated patients compared with controls (16.6 vs. 8.0 months; HR = 0.64, 95% CI 0.41,1.0, p = 0.049), and longer in patients with 1p/19q-codeleted tumors (19.2 vs. 6.2 months, HR = 0.43, 95% CI 0.21,0.89, p = 0.019). Confirmed response rate was 3.9% (PR = 1; REGR = 1), with stable disease observed in 52.9%. At 600 mg/D, mean steady-state imatinib plasma concentration was 2513 ng/ml (95% CI 1831,3195). Grade 3\u20134 adverse events (hematologic, fatigue, GI, hypophosphatemia, or hemorrhage) occurred in 61%. Conclusions: Although adequate plasma levels were achieved, the observed PFS6 of 33% did not reach our pre-defined threshold for success. Although OS was longer in imatinib-treated patients than controls, this finding would require forward validation in a larger cohort. Imatinib might show greater activity in a population enriched for PDGF-dependent pathway activation in tumor tissue

Phase 1/2 trial of temsirolimus and sorafenib in the treatment of patients with recurrent glioblastoma: North Central Cancer Treatment Group Study/Alliance N0572

BACKGROUND: Mitogen-activated protein kinase (MAPK) activation and mammalian target of rapamycin (mTOR)-dependent signaling are hallmarks of glioblastoma. In the current study, the authors conducted a phase 1/2 study of sorafenib (an inhibitor of Raf kinase and vascular endothelial growth factor receptor 2 [VEGFR-2]) and the mTOR inhibitor temsirolimus in patients with recurrent glioblastoma. METHODS: Patients with recurrent glioblastoma who developed disease progression after surgery or radiotherapy plus temozolomide and with 642 prior chemotherapy regimens were eligible. The phase 1 endpoint was the maximum tolerated dose (MTD), using a cohorts-of-3 design. The 2-stage phase 2 study included separate arms for VEGF inhibitor (VEGFi)\u2013naive patients and patients who progressed after prior VEGFi. RESULTS: The MTD was sorafenib at a dose of 200 mg twice daily and temsirolimus at a dose of 20 mg weekly. In the first 41 evaluable patients who were treated at the phase 2 dose, there were 7 who were free of disease progression at 6 months (progression-free survival at 6 months [PFS6]) in the VEGFi-naive group (17.1%); this finding met the prestudy threshold of success. In the prior VEGFi group, only 4 of the first 41 evaluable patients treated at the phase 2 dose achieved PFS6 (9.8%), and this did not meet the prestudy threshold for success. The median PFS for the 2 groups was 2.6 months and 1.9 months, respectively. The median overall survival for the 2 groups was 6.3 months and 3.9 months, respectively. At least 1 adverse event of grade 653 was observed in 75.5% of the VEGFi-naive patients and in 73.9% of the prior VEGFi patients. CONCLUSIONS: The limited activity of sorafenib and temsirolimus at the dose and schedule used in the current study was observed with considerable toxicity of grade 653. Significant dose reductions that were required in this treatment combination compared with tolerated single-agent doses may have contributed to the lack of efficacy. Cancer 2018;124:1455-63. \ua9 2018 American Cancer Society

ATIM-14. ALLIANCE A071101: A PHASE II RANDOMIZED TRIAL COMPARING THE EFFICACY OF HEAT SHOCK PROTEIN PEPTIDE COMPLEX-96 (HSPPC-96) VACCINE GIVEN WITH BEVACIZUMAB VERSUS BEVACIZUMAB ALONE IN THE TREATMENT OF SURGICALLY RESECTABLE RECURRENT GLIOBLASTOMA

Abstract BACKGROUND Heat shock protein vaccines can be used to stimulate anti-tumor immune responses. An autologous vaccine (HSPPC-96) generated from patient resected tumors has been previously studied in single arm phase I/II trials for newly diagnosed and recurrent GBM. Based on promising survival in these studies, a randomized, multi-centered phase II trial of HSPPC-96 for recurrent GBM compared to bevacizumab was undertaken (NCT01814813). METHODS Patients with 1st/2nd recurrence of resectable GBM were enrolled and underwent surgery with generation of HSPPC-96 from autologous tumors. Post-operative eligibility included a volumetric extent of resection ≥90% (by central review) and sufficient tumor to generate a minimum of 4 vaccine doses. Patients were randomized (1:1:1) to receive HSPPC-96 vaccine followed by bevacizumab at subsequent progression vs. concurrent HSPPC-96 vaccine and bevacizumab vs. bevacizumab alone. The primary endpoint was overall survival (OS) aiming to detect a 36% reduction in HR with 85% power and alpha=0.1 for pooled HSPPC-96 groups vs. bevacizumab alone. Planned enrollment was 165 patients (n=55/arm). An interim analysis was pre-planned at 50% of events (65 deaths). Secondary endpoints included progression-free survival and adverse events. RESULTS At final analysis, 90 patients were enrolled with a distribution of 29:30:31. The study was terminated for futility after the interim analysis. In the intention to treat population, OS for the HSPPC-96 treated groups was 7.5 vs. 10.7 months for bevacizumab alone (HR=2.06 [95% CI 1.18–3.60], p=0.008). Among patients treated per protocol (n=73), OS for HSPPC-96 patients was 8.6 vs. 12.3 months (HR=1.99 [95% CI 1.03–3.81], p=0.03). Trends were similar for progression-free survival between groups. HSPPC-96 toxicity was well tolerated with no attributable serious adverse events. CONCLUSIONS The study failed to demonstrate a survival benefit for patients treated with HSPPC-96 alone or in combination with bevacizumab compared to bevacizumab alone. Correlative analyses are ongoing. SUPPORT: U10CA180882, U10CA180821, U10CA180868, U24CA196171