cabozantinib and Glioblastoma

Cabozantinib is a tyrosine kinase inhibitor with activity against vascular endothelial growth factor receptor 2 (VEGFR2) and MET that has demonstrated clinical activity in advanced solid tumors. This open-label, phase II trial evaluated cabozantinib in patients with recurrent or refractory glioblastoma (GBM).. Patients were initially enrolled at a starting dose of 140 mg/day, but the starting dose was amended to 100 mg/day because of toxicity. Treatment continued until disease progression or unacceptable toxicity. The primary endpoint was objective response rate assessed by an independent radiology facility using modified Response Assessment in Neuro-Oncology criteria. Additional endpoints included duration of response, 6-month and median progression-free survival, overall survival, and safety.. Among 152 patients naive to prior antiangiogenic therapy, the objective response rate was 17.6% and 14.5% in the 140 mg/day and 100 mg/day groups, respectively, which did not meet the predefined statistical target for success. The proportions of patients alive and progression free at 6 months were 22.3% and 27.8%, respectively. Median progression-free survival was 3.7 months in both groups, and median overall survival was 7.7 months and 10.4 months, respectively. The incidence of grade 3/4 adverse events (AEs) was 79.4% and 84.7% in the 140 mg/day and 100 mg/day groups, respectively, and dose reductions due to AEs were experienced by 61.8% and 72.0%, respectively. Common grade 3/4 AEs included fatigue, diarrhea, and palmar-plantar erythrodysesthesia syndrome.. Cabozantinib showed evidence of clinical activity in patients with recurrent GBM naive to antiangiogenic therapy, although the predefined statistical target for success was not met. At the starting doses assessed, AEs were frequently managed with dose reductions.. NCT00704288 (https://www.clinicaltrials.gov/ct2/show/NCT00704288).

Topics: Adult; Aged; Angiogenesis Inhibitors; Anilides; Data Analysis; Disease-Free Survival; Female; Glioblastoma; Humans; Kaplan-Meier Estimate; Male; Middle Aged; Protein Kinase Inhibitors; Pyridines; Treatment Outcome

Cabozantinib is a potent, multitarget inhibitor of MET and vascular endothelial growth factor receptor 2 (VEGFR2). This open-label, phase II trial evaluated cabozantinib in patients with recurrent or progressive glioblastoma (GBM).. Patients were initially enrolled to a starting cabozantinib dose of 140 mg/day, but the starting dose was amended to 100 mg/day because of safety concerns. Treatment continued until disease progression or unacceptable toxicity. The primary endpoint was objective response rate, assessed by an independent radiology facility using modified Response Assessment in Neuro-Oncology criteria. Additional endpoints included duration of response, 6-month and median progression-free survival, overall survival, glucocorticoid use, and safety.. Among 222 patients enrolled, 70 had received prior antiangiogenic therapy. Herein, we report results in this subset of 70 patients. The objective response rate was 4.3%, and the median duration of response was 4.2 months. The proportion of patients alive and progression free at 6 months was 8.5%. Median progression-free survival was 2.3 months, and median overall survival was 4.6 months. The most common adverse events reported in all patients, regardless of dose group, included fatigue (74.3%), diarrhea (47.1%), increased alanine aminotransferase (37.1%), headache (35.7%), hypertension (35.7%), and nausea (35.7%); overall, 34 (48.6%) patients experienced adverse events that resulted in dose reductions.. Cabozantinib treatment appeared to have modest clinical activity with a 4.3% response rate in patients who had received prior antiangiogenic therapy for GBM.. NCT00704288 (https://www.clinicaltrials.gov/ct2/show/NCT00704288).

Topics: Adult; Aged; Angiogenesis Inhibitors; Anilides; Data Analysis; Disease-Free Survival; Female; Glioblastoma; Humans; Male; Middle Aged; Pyridines; Treatment Outcome

To overcome challenges with traditional response assessment in anti-angiogenic agents, the current study uses T1 subtraction maps to quantify volumetric radiographic response in monotherapy with cabozantinib, an orally bioavailable tyrosine kinase inhibitor with activity against vascular endothelial growth factor receptor 2 (VEGFR2), hepatocyte growth factor receptor (MET), and AXL, in an open-label, phase II trial in patients with recurrent glioblastoma (GBM) (NCT00704288).. A total of 108 patients with adequate imaging data and confirmed recurrent GBM were included in this retrospective study from a phase II multicenter trial of cabozantinib monotherapy (XL184-201) at either 100 mg (N = 87) or 140 mg (N = 21) per day. Contrast enhanced T1-weighted digital subtraction maps were used to define volume of contrast-enhancing tumor at baseline and subsequent follow-up time points. Volumetric radiographic response (>65% reduction in contrast-enhancing tumor volume from pretreatment baseline tumor volume sustained for more than 4 wk) was tested as an independent predictor of overall survival (OS).. Volumetric response rate for all therapeutic doses was 38.9% (41.4% and 28.6% for 100 mg and 140 mg doses, respectively). A log-linear association between baseline tumor volume and OS (P = 0.0006) and a linear correlation between initial change in tumor volume and OS (P = 0.0256) were observed. A significant difference in OS was observed between responders (median OS = 20.6 mo) and nonresponders (median OS = 8.0 mo) (hazard ratio [HR] = 0.3050, P < 0.0001). Multivariable analyses showed that continuous measures of baseline tumor volume (HR = 1.0233, P < 0.0001) and volumetric response (HR = 0.2240, P < 0.0001) were independent predictors of OS.. T1 subtraction maps provide value in determining response in recurrent GBM treated with cabozantinib and correlated with survival benefit.

Topics: Adult; Aged; Anilides; Brain Neoplasms; Contrast Media; Female; Follow-Up Studies; Glioblastoma; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Neoplasm Recurrence, Local; Prognosis; Protein Kinase Inhibitors; Pyridines; Retrospective Studies; Survival Rate; Tumor Burden; Young Adult

Cabozantinib inhibits mesenchymal-epithelial transition factor (MET) and vascular endothelial growth factor receptor 2 (VEGFR2) and has demonstrated activity in patients with recurrent glioblastoma, warranting evaluation of the addition of cabozantinib to radiotherapy (RT) and temozolomide (TMZ) for patients with newly diagnosed high-grade glioma.. Cabozantinib doses of 40 mg and 60 mg were explored. Patients on the concurrent treatment arm received cabozantinib daily with standard TMZ and after RT continued cabozantinib daily with adjuvant TMZ. In the maintenance arm, patients who completed RT and ≥1 adjuvant cycle of TMZ continued adjuvant TMZ with added cabozantinib (3 schedules: days 1-28, days 1-14, or days 8-21).. A total of 26 patients (25 with recurrent glioblastoma and 1 patient with anaplastic astrocytoma) aged 30 to 72 years were enrolled (10 to the concurrent arm and 16 to the maintenance arm). The median number of post-RT TMZ cycles was 4.5 (range, 0-14 cycles) in the concurrent arm and 5.5 (range, 1-12 cycles) in the maintenance arm. Cabozantinib at a dose of 60 mg daily was the maximum administered dose and a dose of 40 mg daily was determined to be the maximum tolerated dose for both treatment arms (schedule of days 1-28). The most frequent grade 3/4 adverse events were thrombocytopenia (31% of patients), leukopenia (27% of patients, including 5 patients with neutropenia), and deep vein thrombosis and/or pulmonary embolism (23% of patients) (adverse events were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0]).. Cabozantinib at a dose of 40 mg daily with RT plus TMZ and post-RT TMZ for patients with newly diagnosed high-grade glioma was generally well tolerated, and demonstrated no pharmacokinetic interactions with concurrent TMZ. Given the strong theoretical rationale for combining anti-VEGF and anti-MET activity with standard therapy, cabozantinib at a dose of 40 mg daily warrants evaluation in combination with standard therapy for patients with newly diagnosed glioblastoma.

Topics: Adult; Aged; Alanine Transaminase; Anilides; Antineoplastic Combined Chemotherapy Protocols; Aspartate Aminotransferases; Astrocytoma; Brain Neoplasms; Chemoradiotherapy; Chemoradiotherapy, Adjuvant; Constipation; Dacarbazine; Diarrhea; Fatigue; Female; Glioblastoma; Humans; Hypertension; L-Lactate Dehydrogenase; Leukopenia; Maintenance Chemotherapy; Male; Maximum Tolerated Dose; Middle Aged; Nausea; Neoplasm Grading; Neurosurgical Procedures; Neutropenia; Pyridines; Temozolomide; Thrombocytopenia; Treatment Outcome

Topics: Animals; Antineoplastic Agents; Female; Glioblastoma; Humans; Mice, Nude; Microsomes, Liver; Molecular Docking Simulation; Molecular Structure; Naphthyridines; Protein Binding; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-met; Quinazolines; Rats; Structure-Activity Relationship; Thermodynamics; Xenograft Model Antitumor Assays

Monotherapy clinical trials with mutation-targeted kinase inhibitors, despite some success in other cancers, have yet to impact glioblastoma (GBM). Besides insufficient blood-brain barrier penetration, combinations are key to overcoming obstacles such as intratumoral heterogeneity, adaptive resistance, and the epistatic nature of tumor genomics that cause mutation-targeted therapies to fail. With now hundreds of potential drugs, exploring the combination space clinically and preclinically is daunting. We are building a simulation-based approach that integrates patient-specific data with a mechanistic computational model of pan-cancer driver pathways (receptor tyrosine kinases, RAS/RAF/ERK, PI3K/AKT/mTOR, cell cycle, apoptosis, and DNA damage) to prioritize drug combinations by their simulated effects on tumor cell proliferation and death. Here we illustrate a first step, tailoring the model to 14 GBM patients from The Cancer Genome Atlas defined by an mRNA-seq transcriptome, and then simulating responses to three promiscuous FDA-approved kinase inhibitors (bosutinib, ibrutinib, and cabozantinib) with evidence for blood-brain barrier penetration. The model captures binding of the drug to primary targets and off-targets based on published affinity data and simulates responses of 100 heterogeneous tumor cells within a patient. Single drugs are marginally effective or even counterproductive. Common copy number alterations (PTEN loss, EGFR amplification, and NF1 loss) have a negligible correlation with single-drug or combination efficacy, reinforcing the importance of postgenetic approaches that account for kinase inhibitor promiscuity to match drugs to patients. Drug combinations tend to be either cytostatic or cytotoxic, but seldom both, highlighting the need for considering targeted and nontargeted therapy. Although we focus on GBM, the approach is generally applicable.

Topics: Adenine; Anilides; Aniline Compounds; Antineoplastic Agents; Apoptosis; Blood-Brain Barrier; Cell Cycle; Cell Proliferation; Central Nervous System Neoplasms; Clinical Trials as Topic; Computer Simulation; Drug Discovery; Drug Therapy, Combination; Genomics; Glioblastoma; Humans; Models, Theoretical; Nitriles; Piperidines; Protein-Tyrosine Kinases; Pyrazoles; Pyridines; Pyrimidines; Quinolines; RNA, Messenger; Stochastic Processes; Transcriptome

Topics: Angiogenesis Inhibitors; Anilides; Brain Neoplasms; Glioblastoma; Humans; Neovascularization, Pathologic; Prognosis; Pyridines; Survival Rate

Anti-angiogenic treatment of glioblastoma with Vascular Endothelial Growth Factor (VEGF)- or VEGF Receptor 2 (VEGFR2) inhibitors normalizes tumor vessels, resulting in a profound radiologic response and improved quality of life. This approach however does not halt tumor progression by diffuse infiltration, as this phenotype is less angiogenesis dependent. Combined inhibition of angiogenesis and diffuse infiltrative growth would therefore be a more effective treatment approach in these tumors. The HGF/c-MET axis is important in both angiogenesis and cell migration in several tumor types including glioma. We therefore analyzed the effects of the c-MET- and VEGFR2 tyrosine kinase inhibitor cabozantinib (XL184, Exelixis) on c-MET positive orthotopic E98 glioblastoma xenografts, which routinely present with angiogenesis-dependent areas of tumor growth, as well as diffuse infiltrative growth. In in vitro cultures of E98 cells, cabozantinib effectively inhibited c-MET phosphorylation, concomitant with inhibitory effects on AKT and ERK1/2 phosphorylation, and cell proliferation and migration. VEGFR2 activation in endothelial cells was also effectively inhibited in vitro. Treatment of BALB/c nu/nu mice carrying orthotopic E98 xenografts resulted in a significant increase in overall survival. Cabozantinib effectively inhibited angiogenesis, resulting in increased hypoxia in angiogenesis-dependent tumor areas, and induced vessel normalization. Yet, tumors ultimately escaped cabozantinib therapy by diffuse infiltrative outgrowth via vessel co-option. Of importance, in contrast to the results from in vitro experiments, in vivo blockade of c-MET activation was incomplete, possibly due to multiple factors including restoration of the blood-brain barrier resulting from cabozantinib-induced VEGFR2 inhibition. In conclusion, cabozantinib is a promising therapy for c-MET positive glioma, but improving delivery of the drug to the tumor and/or the surrounding tissue may be needed for full activity.

Topics: Anilides; Animals; Drug Delivery Systems; Glioblastoma; Humans; Mice; Mice, Inbred BALB C; Neovascularization, Physiologic; Phosphorylation; Proto-Oncogene Proteins c-met; Pyridines; Transplantation, Heterologous; Tumor Cells, Cultured; Vascular Endothelial Growth Factor Receptor-2