Phase 1 dose-escalation study of SEA-CD40: a non-fucosylated CD40 agonist, in advanced solid tumors and lymphomas.

BACKGROUND: SEA-CD40 is an investigational, non-fucosylated, humanized monoclonal IgG1 antibody that activates CD40, an immune-activating tumor necrosis factor receptor superfamily member. SEA-CD40 exhibits enhanced binding to activating FcγRIIIa, possibly enabling greater immune stimulation than other CD40 agonists. A first-in-human phase 1 trial was conducted to examine safety, pharmacokinetics, and pharmacodynamics of SEA-CD40 monotherapy in patients with advanced solid tumors and lymphoma. METHODS: SEA-CD40 was administered intravenously to patients with solid tumors or lymphoma in 21-day cycles with standard 3+3 dose escalation at 0.6, 3, 10, 30, 45, and 60 µg/kg. An intensified dosing regimen was also studied. The primary objectives of the study were to evaluate the safety and tolerability and identify the maximum tolerated dose of SEA-CD40. Secondary objectives included evaluation of the pharmacokinetic parameters, antitherapeutic antibodies, pharmacodynamic effects and biomarker response, and antitumor activity. RESULTS: A total of 67 patients received SEA-CD40 including 56 patients with solid tumors and 11 patients with lymphoma. A manageable safety profile was observed, with predominant adverse events of infusion/hypersensitivity reactions (IHRs) reported in 73% of patients. IHRs were primarily ≤grade 2 with an incidence associated with infusion rate. To mitigate IHRs, a standardized infusion approach was implemented with routine premedication and a slowed infusion rate. SEA-CD40 infusion resulted in potent immune activation, illustrated by dose dependent cytokine induction with associated activation and trafficking of innate and adaptive immune cells. Results suggested that doses of 10-30 µg/kg may result in optimal immune activation. SEA-CD40 monotherapy exhibited evidence of antitumor activity, with a partial response in a patient with basal cell carcinoma and a complete response in a patient with follicular lymphoma. CONCLUSIONS: SEA-CD40 was tolerable as monotherapy and induced potent dose dependent immune cell activation and trafficking consistent with immune activation. Evidence of monotherapy antitumor activity was observed in patients with solid tumors and lymphoma. Further evaluation of SEA-CD40 is warranted, potentially as a component of a combination regimen. TRIAL REGISTRATION NUMBER: NCT02376699.

Phase IB Study of GITR Agonist Antibody TRX518 Singly and in Combination with Gemcitabine, Pembrolizumab, or Nivolumab in Patients with Advanced Solid Tumors.

PURPOSE: TRX518 is a mAb engaging the glucocorticoid-induced TNF receptor-related protein (GITR). This open-label, phase I study (TRX518-003) evaluated the safety and efficacy of repeated dose TRX518 monotherapy and in combination with gemcitabine, pembrolizumab, or nivolumab in advanced solid tumors. PATIENTS AND METHODS: TRX518 monotherapy was dose escalated (Part A) and expanded (Part B) up to 4 mg/kg loading, 1 mg/kg every 3 weeks. Parts C-E included dose-escalation (2 and 4 mg/kg loading followed by 1 mg/kg) and dose-expansion (4 mg/kg loading) phases with gemcitabine (Part C), pembrolizumab (Part D), or nivolumab (Part E). Primary endpoints included incidence of dose-limiting toxicities (DLT), serious adverse events (SAE), and pharmacokinetics. Secondary endpoints were efficacy and pharmacodynamics. RESULTS: A total of 109 patients received TRX518: 43 (Parts A+B), 30 (Part C), 26 (Part D), and 10 (Part E), respectively. A total of 67% of patients in Parts D+E had received prior anti-PD(L)1 or anti-CTLA-4. No DLTs, treatment-related SAEs, and/or grade 4 or 5 AEs were observed with TRX518 monotherapy. In Parts C-E, no DLTs were observed, although TRX518-related SAEs were reported in 3.3% (Part C) and 10.0% (Part E), respectively. Objective response rate was 3.2%, 3.8%, 4%, and 12.5% in Parts A+B, C, D, and E, respectively. TRX518 affected peripheral and intratumoral regulatory T cells (Treg) with different kinetics depending on the combination regimen. Responses with TRX518 monotherapy+anti-PD1 combination were associated with intratumoral Treg reductions and CD8 increases and activation after treatment. CONCLUSIONS: TRX518 showed an acceptable safety profile with pharmacodynamic activity. Repeated dose TRX518 monotherapy and in combination resulted in limited clinical responses associated with immune activation. See related commentary by Hernandez-Guerrero and Moreno, p. 3905.

Mogamulizumab in Combination with Nivolumab in a Phase I/II Study of Patients with Locally Advanced or Metastatic Solid Tumors.

PURPOSE: The aim of the study was to determine safety, antitumor activity, and pharmacodynamic profile of mogamulizumab, an anti-CCR4 monoclonal antibody targeting effector regulatory T cells (Treg) in combination with the checkpoint inhibitor nivolumab in patients with locally advanced or metastatic solid tumors. PATIENTS AND METHODS: This was a multicenter, dose-finding (phase I), and dose expansion (phase II) study (NCT02705105) in patients with locally advanced or metastatic solid tumors. There were no dose-limiting toxicities in phase I with mogamulizumab 1 mg/kg every week for cycle 1 followed by 1 mg/kg every 2 weeks plus nivolumab 240 mg every 2 weeks intravenously, and cohort expansion occurred at this dose level. RESULTS: All 114 patients treated with mogamulizumab 1 mg/kg plus nivolumab 240 mg in phases I (n = 4) and II (n = 110) were assessed for safety and efficacy. Mogamulizumab plus nivolumab showed acceptable safety and tolerability. Objective response rate was 10.5% [95% confidence interval (CI), 5.6-17.7; 3 complete and 9 partial responses]. Disease control rate was 36.8%. Median duration of response was 14.4 months. Median progression-free survival was 2.6 (95% CI, 2.3-3.1) months, and median overall survival was 9.5 (95% CI, 5.9-13.5) months. CONCLUSIONS: Combination of mogamulizumab with nivolumab for treatment of patients with locally advanced or metastatic solid tumors did not result in enhanced efficacy. Tolerability of mogamulizumab 1 mg/kg plus nivolumab 240 mg was acceptable.

Phase II trial of the IDO pathway inhibitor indoximod plus pembrolizumab for the treatment of patients with advanced melanoma.

BACKGROUND: The indoleamine 2,3-dioxygenase (IDO) pathway is a key counter-regulatory mechanism that, in cancer, is exploited by tumors to evade antitumor immunity. Indoximod is a small-molecule IDO pathway inhibitor that reverses the immunosuppressive effects of low tryptophan (Trp) and high kynurenine (Kyn) that result from IDO activity. In this study, indoximod was used in combination with a checkpoint inhibitor (CPI) pembrolizumab for the treatment for advanced melanoma. METHODS: Patients with advanced melanoma were enrolled in a single-arm phase II clinical trial evaluating the addition of indoximod to standard of care CPI approved for melanoma. Investigators administered their choice of CPI including pembrolizumab (P), nivolumab (N), or ipilimumab (I). Indoximod was administered continuously (1200 mg orally two times per day), with concurrent CPI dosed per US Food and Drug Administration (FDA)-approved label. RESULTS: Between July 2014 and July 2017, 131 patients were enrolled. (P) was used more frequently (n=114, 87%) per investigator's choice. The efficacy evaluable population consisted of 89 patients from the phase II cohort with non-ocular melanoma who received indoximod combined with (P).The objective response rate (ORR) for the evaluable population was 51% with confirmed complete response of 20% and disease control rate of 70%. Median progression-free survival was 12.4 months (95% CI 6.4 to 24.9). The ORR for Programmed Death-Ligand 1 (PD-L1)-positive patients was 70% compared with 46% for PD-L1-negative patients. The combination was well tolerated, and side effects were similar to what was expected from single agent (P). CONCLUSION: In this study, the combination of indoximod and (P) was well tolerated and showed antitumor efficacy that is worth further evaluation in selected patients with advanced melanoma.

Assessment of effects of repeated oral doses of fedratinib on inhibition of cytochrome P450 activities in patients with solid tumors using a cocktail approach.

PURPOSE: Fedratinib, an oral selective kinase inhibitor with activity against both wild type and mutationally activated Janus kinase 2, has been approved for the treatment of adult patients with intermediate-2 or high-risk myelofibrosis by the US Food and Drug Administration. In vitro studies indicated that fedratinib was an inhibitor of several cytochrome P450 (CYP) enzymes. The primary objective of this study was to evaluate the effects of repeated doses of fedratinib on the activity of CYP2D6, CYP2C19, and CYP3A4 in patients with solid tumors using a CYP probe cocktail. METHODS: An open-label, one-sequence, two-period, two-treatment crossover study was conducted. Patients were administered a single oral dose cocktail of metoprolol (100 mg), omeprazole (20 mg), and midazolam (2 mg) used as probe substrates for CYP2D6, CYP2C19, and CYP3A4 enzyme activities, respectively, without fedratinib on Day -1 or with fedratinib on Day 15. RESULTS: Coadministration of 500 mg once-daily doses of fedratinib for 15 days increased the mean area under the plasma concentration-time curve from time zero to infinity following a single-dose cocktail containing metoprolol (CYP2D6 substrate), omeprazole (CYP2C19 substrate), and midazolam (CYP3A4 substrate) by 1.77-fold (90% confidence interval [CI] 1.27-2.47) for metoprolol, 2.82-fold (90% CI 2.26-3.53) for omeprazole, and 3.84-fold (90% CI 2.62-5.63) for midazolam, respectively. The mean plasma Day 14/Day 1 ratio of 4ß-hydroxycholesterol, an endogenous biomarker of CYP3A4 activity, was 0.59 (90% CI 0.54-0.66), suggesting a net inhibition of CYP3A4 by fedratinib. CONCLUSION: Fedratinib is a weak inhibitor of CYP2D6, and a moderate inhibitor of CYP2C19 and CYP3A4. These results serve as the basis for dose modifications of these CYP substrate drugs when co-administered with fedratinib.

A phase 1 study of PF-06840003, an oral indoleamine 2,3-dioxygenase 1 (IDO1) inhibitor in patients with recurrent malignant glioma.

Background PF-06840003 is a highly selective indoleamine 2, 3-dioxygenase (IDO1) inhibitor with antitumor effects in preclinical models. This first-in-human phase 1 study evaluated safety, pharmacokinetics/pharmacodynamics, and preliminary efficacy in recurrent malignant glioma to determine the maximum tolerated dose (MTD) or recommended phase 2 dose (RP2D). Methods Patients (N = 17) received oral PF-06840003 in four dose-escalation groups: 125 mg once-daily (QD; n = 2); 250 mg QD (n = 4); 250 mg twice-daily (BID; n = 3); 500 mg BID (n = 8). A modified toxicity probability interval method determined the MTD. Results Four patients experienced serious adverse events (SAEs); one with treatment-related SAEs (grade 4 alanine and aspartate aminotransferase elevations). The dose-limiting toxicity (DLT) rate at 500 mg BID was 12.5% (n = 1/8); the MTD was not reached. Following PF-06840003 dosing, median time to maximum plasma concentration for the active enantiomer PF-06840002 was 1.5-3.0 hr and mean elimination half-life was 2 to 4 hr (Cycle 1 Day 1). Urinary recovery of PF-06840002 was low (< 1%). At 500 mg BID, maximum mean percentage inhibition of 13C10 kynurenine vs endogenous kynurenine was 75% vs 24%. PF-06840002 CSF-to-plasma ratio was 1.00. Disease control occurred in eight patients (47%). Mean duration of stable disease (SD) was 32.1 (12.1-72.3) weeks. Two patients with SD discontinued the study at 450 and 561 days and continued PF-06840003 on compassionate use. Conclusion PF­06840003 up to 500 mg BID was generally well tolerated with evidence of a pharmacodynamic effect and durable clinical benefit in a subset of patients with recurrent malignant glioma. ClinicalTrials.gov, NCT02764151, registered April 2016.

Precision Oncology for Cancer Immunotherapies in Early-Phase Clinical Trials.

The clinical development of cancer drugs is rapidly moving from empirical "one drug fits all" or development-by-tumor-type approaches towards more personalized treatment models. A deeper understanding of cancer and the immune system, novel technologies, and powerful analytics have fueled an increase in precision oncology approaches integrating the molecular profiles of the tumor with the clinical profile of the patient. While this approach has been successful for targeted therapies, the complex mode of action of immunotherapies will likely require integration of clinical profiling with more comprehensive profiling of the tumor, of the tumor microenvironment, and of the immune system of the patient. Integration of precision oncology into clinical research for immunotherapies is viewed as a means to better select patients in the early clinical phase of drug development to (1) maximize the benefit-to-risk ratio for the patient, (2) generate early proof of concept and proof of relevance for the investigational drug, and (3) inform on how to best combine or sequence the therapeutic with other drugs. Here we discuss the upsides and challenges of incorporating precision immuno-oncology into early-phase clinical trials.

Alpha-Emitters and Targeted Alpha Therapy in Oncology: from Basic Science to Clinical Investigations.

Alpha-emitters are radionuclides that decay through the emission of high linear energy transfer α-particles and possess favorable pharmacologic profiles for cancer treatment. When coupled with monoclonal antibodies, peptides, small molecules, or nanoparticles, the excellent cytotoxic capability of α-particle emissions has generated a strong interest in exploring targeted α-therapy in the pre-clinical setting and more recently in clinical trials in oncology. Multiple obstacles have been overcome by researchers and clinicians to accelerate the development of targeted α-therapies, especially with the recent improvement in isotope production and purification, but also with the development of innovative strategies for optimized targeting. Numerous studies have demonstrated the in vitro and in vivo efficacy of the targeted α-therapy. Radium-223 (223Ra) dichloride (Xofigo®) is the first α-emitter to have received FDA approval for the treatment of prostate cancer with metastatic bone lesions. There is a significant increase in the number of clinical trials in oncology using several radionuclides such as Actinium-225 (225Ac), Bismuth-213 (213Bi), Lead-212 (212Pb), Astatine (211At) or Radium-223 (223Ra) assessing their safety and preliminary activity. This review will cover their therapeutic application as well as summarize the investigations that provide the foundation for further clinical development.

A Phase Ib Study of the Dual PI3K/mTOR Inhibitor Dactolisib (BEZ235) Combined with Everolimus in Patients with Advanced Solid Malignancies.

BACKGROUND: The combination of everolimus and the imidazoquinoline derivative, BEZ235 (dactolisib), a dual PI3K/mTOR inhibitor, demonstrated synergy in a preclinical model. OBJECTIVE: To establish clinical feasibility, a phase Ib dose-escalation trial investigating safety and pharmacokinetics of this combination in patients with advanced tumors was performed. PATIENTS AND METHODS: BEZ235 was orally administered daily in escalating doses of 200, 400, and 800 mg along with everolimus at 2.5 mg daily in 28-day cycles. Nineteen patients were enrolled. Adverse events and tumor responses were evaluated using CTCAE v4.0 and RECIST 1.1, respectively. Pharmacokinetic analyses were performed. RESULTS: Common toxicities observed included fatigue, diarrhea, nausea, mucositis, and elevated liver enzymes. No confirmed responses were observed. BEZ235 pharmacokinetics exhibited dose-proportional increases in Cmax and AUC0-24 over the three doses, with high inter-individual variability. Non-compartmental and population pharmacokinetic-based simulations indicated significant increases in everolimus Cmax and AUC0-24 on day 28 and decreased clearance to 13.41 L/hr. CONCLUSIONS: The combination of BEZ235 and everolimus demonstrated limited efficacy and tolerance. BEZ235 systemic exposure increased in a dose-proportional manner while oral bioavailability was quite low, which may be related to gastrointestinal-specific toxicity. The changes in steady-state pharmacokinetics of everolimus with BEZ235 highlight potential drug-drug interactions when these two drugs are administered together. Clinicaltrials.gov: NCT01508104.

Safety and pharmacokinetics of cabazitaxel in patients with hepatic impairment: a phase I dose-escalation study.

PURPOSE: Cabazitaxel has not been studied in patients with hepatic impairment (HI). This phase I study assessed cabazitaxel safety and pharmacokinetics in patients with HI. METHODS: Patients with advanced, non-hematologic cancer, and normal hepatic function (Cohort 1: C-1), or mild (C-2), moderate (C-3), severe (C-4) HI received cabazitaxel starting doses of 25, 20, 10, and 10 mg/m2, respectively. Doses were escalated in patients with HI based on Cycle 1 dose-limiting toxicities (DLTs). Adverse events and the cabazitaxel pharmacokinetic profile were assessed. RESULTS: In C-2, three patients receiving cabazitaxel 25 mg/m2 experienced DLTs; maximum tolerated dose (MTD) was 20 mg/m2. In C-3, two patients receiving 20 mg/m2 experienced DLTs; MTD was 15 mg/m2. C-4 was discontinued early due to DLTs. The most frequent cabazitaxel-related, grade 3-4 toxicity was neutropenia (42%). Cabazitaxel clearance normalized to body surface area (CL/BSA) was lower in C-1 (geometric mean [GM] 13.4 L/h/m2) than expected (26.4 L/h/m2), but similar in C-2 (23.5 L/h/m2) and C-3 (27.9 L/h/m2). CL/BSA in C-4 was 18.1 L/h/m2. Compared with C-2, CL/BSA increased 19% in C-3 (GM ratio 1.19; 90% CI 0.74-1.91), but decreased 23% in C-4 (0.77; 0.39-1.53). Cabazitaxel free fraction was unaltered. No significant correlation was found between grade 3-4 toxicities and pharmacokinetic parameters. CONCLUSIONS: Mild-moderate HI did not cause substantial decline in cabazitaxel clearance. Cabazitaxel dose reductions in patients with mild-moderate HI, and a contraindication in patients with severe HI, are justified based on safety data.

Effect of Renal Impairment on the Pharmacokinetics and Safety of Axitinib.

BACKGROUND: Axitinib, an inhibitor of vascular endothelial growth factor (VEGF) receptors, is approved as second-line treatment for advanced renal cell carcinoma (RCC). Agents targeting the VEGF pathway may induce renal toxicities, which may be influenced by pre-existing renal dysfunction. OBJECTIVE: The objective was to characterize axitinib pharmacokinetics and safety in patients with renal impairment. PATIENTS AND METHODS: Effect of renal function (baseline creatinine clearance [CrCL]) on axitinib clearance was evaluated in a population pharmacokinetic model in 207 patients with advanced solid tumors who received a standard axitinib starting dose, and in 383 healthy volunteers. Axitinib safety according to baseline CrCL was assessed in previously treated patients with RCC (n = 350) who received axitinib in the phase 3 AXIS study. RESULTS: Median axitinib clearance was 14.0, 10.7, 12.3, 7.81, and 12.6 L/h, respectively, in individuals with normal renal function (≥90 ml/min; n = 381), mild renal impairment (60-89 ml/min; n = 139), moderate renal impairment (30-59 ml/min; n = 64), severe renal impairment (15-29 ml/min; n = 5), and end-stage renal disease (<15 ml/min; n = 1). The population pharmacokinetic model adequately predicted axitinib clearance in individuals with severe renal impairment or end-stage renal disease. Grade ≥3 adverse events (AEs) were reported in 63 % of patients with normal renal function or mild impairment, 77 % with moderate impairment, and 50 % with severe impairment; study discontinuations due to AEs were 10 %, 11 %, and 0 %, respectively. CONCLUSIONS: Axitinib pharmacokinetics and safety were similar regardless of baseline renal function; no starting-dose adjustment is needed for patients with pre-existing mild to severe renal impairment.

High-Dose Sirolimus and Immune-Selective Pentostatin plus Cyclophosphamide Conditioning Yields Stable Mixed Chimerism and Insufficient Graft-versus-Tumor Responses.

PURPOSE: We hypothesized that lymphoid-selective host conditioning and subsequent adoptive transfer of sirolimus-resistant allogeneic T cells (T-Rapa), when combined with high-dose sirolimus drug therapy in vivo, would safely achieve antitumor effects while avoiding GVHD. EXPERIMENTAL DESIGN: Patients (n = 10) with metastatic renal cell carcinoma (RCC) were accrued because this disease is relatively refractory to high-dose conditioning yet may respond to high-dose sirolimus. A 21-day outpatient regimen of weekly pentostatin (P; 4 mg/m(2)/dose) combined with daily, dose-adjusted cyclophosphamide (C; ≤200 mg/d) was designed to deplete and suppress host T cells. After PC conditioning, patients received matched sibling, T-cell-replete peripheral blood stem cell allografts, and high-dose sirolimus (serum trough target, 20-30 ng/mL). To augment graft-versus-tumor (GVT) effects, multiple T-Rapa donor lymphocyte infusions (DLI) were administered (days 0, 14, and 45 posttransplant), and sirolimus was discontinued early (day 60 posttransplant). RESULTS: PC conditioning depleted host T cells without neutropenia or infection and facilitated donor engraftment (10 of 10 cases). High-dose sirolimus therapy inhibited multiple T-Rapa DLI, as evidenced by stable mixed donor/host chimerism. No antitumor responses were detected by RECIST criteria and no significant classical acute GVHD was observed. CONCLUSIONS: Immune-selective PC conditioning represents a new approach to safely achieve alloengraftment without neutropenia. However, allogeneic T cells generated ex vivo in sirolimus are not resistant to the tolerance-inducing effects of in vivo sirolimus drug therapy, thereby cautioning against use of this intervention in patients with refractory cancer.

Axitinib: from preclinical development to future clinical perspectives in renal cell carcinoma.

INTRODUCTION: Based on extensive preclinical data and abundant evidence for clinical activity, vascular endothelial growth factor receptor (VEGFR) inhibitors are currently standard of care for metastatic renal cell carcinoma (mRCC). Axitinib is one of the most selective molecules in the class of anti-angiogenic agents, which confers an optimal profile between its safety and anti-cancer activity spectrum. AREA COVERED: In this review, the authors discuss the different stages that lead to the approval of axitinib in the clinic as well as the current perspectives for its clinical use with other promising therapies in mRCC such as immune checkpoint inhibitors and vaccines. EXPERT OPINION: In 2015, axitinib has emerged as one of the major agents used in mRCC. Based on robust preclinical data, this highly specific VEGFR inhibitor continues to be evaluated in different indications, including the adjuvant setting but also sequential administration with other molecularly targeted agents or combinations with immune therapies.

Phase I dose-escalation study of cabazitaxel administered in combination with gemcitabine in patients with metastatic or unresectable advanced solid malignancies.

Taxane-gemcitabine combinations have demonstrated antitumor activity. This phase I study (NCT01001221) aimed to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs) of cabazitaxel plus gemcitabine and to assess the preliminary efficacy of this combination. The patients included had metastatic or unresectable solid tumors and had exhausted standard treatment. Cohorts of three to six patients received cabazitaxel (15-20 mg/m) before (part 1a) or after (part 1b) gemcitabine (700-1000 mg/m) on Day 1 and gemcitabine alone on Day 8. Prophylactic growth factors were not allowed in cycle 1. In part 1a (n=12), five patients received 20 mg/m cabazitaxel plus 1000 mg/m gemcitabine (20/1000), five received 15/900, two received 15/700. In part 1b, all six patients received the lowest dose (700/15). At all doses, two or more patients experienced a DLT, regardless of administration sequence, including febrile neutropenia (n=4), grade 4 neutropenia (n=2), grade 4 thrombocytopenia (n=2), and grade 3 aspartate transaminase increase (n=1). The MTD was not established as all cohorts exceeded the MTD by definition. All patients experienced an adverse event; the most frequent all-grade nonhematologic events were fatigue (66.7%), decreased appetite (50.0%), and diarrhea (44.4%). The most frequent grade 3-4 hematologic abnormalities were neutropenia (83.3%), leukopenia (77.8%), and lymphopenia (72.2%). Toxicity was sequence-independent but appeared worse with gemcitabine followed by cabazitaxel. Durable partial responses were observed in three patients (prostate cancer, appendiceal cancer, and melanoma). The unacceptable DLTs with cabazitaxel plus gemcitabine, at doses reduced more than 25% from single-agent doses, preclude further investigation.

Phase I study of cabazitaxel plus cisplatin in patients with advanced solid tumors: study to evaluate the impact of cytochrome P450 3A inhibitors (aprepitant, ketoconazole) or inducers (rifampin) on the pharmacokinetics of cabazitaxel.

PURPOSE: Cabazitaxel is primarily metabolized by CYP3A. This study evaluated the impact of moderate/strong CYP3A inhibitors [aprepitant (Study Part 2); ketoconazole (Study Part 3)] or strong CYP3A inducers [rifampin (Study Part 4)] on the pharmacokinetics of cabazitaxel. METHODS: Adult patients received IV cabazitaxel/cisplatin 15/75 mg/m(2) on Day 1 of 3-week cycles (5/75 mg/m(2) in Cycles 1 and 2 of Part 3 to allow a safety margin to the cabazitaxel MTD). Patients received repeated oral doses of aprepitant, ketoconazole or rifampin before/during Cycle 2. Cabazitaxel clearance was the primary endpoint; clearance and area under the plasma concentration-time curve (AUC) were normalized to body surface area and dose, respectively. RESULTS: The PK population included 13 (Part 2), 23 (Part 3) and 21 patients (Part 4). Repeated aprepitant administration did not affect cabazitaxel clearance [geometric mean ratio (GMR) 0.98; 90 % confidence interval (CI) 0.80-1.19]. Repeated ketoconazole administration resulted in 20 % decrease in cabazitaxel clearance (GMR 0.80; 90 % CI 0.55-1.15), associated with 25 % increase in AUC (GMR 1.25; 90 % CI 0.86-1.81). Repeated rifampin administration resulted in 21 % increase in cabazitaxel clearance (GMR 1.21; 90 % CI 0.95-1.53), associated with 17 % decrease in AUC (GMR 0.83; 90 % CI 0.65-1.05). The GMR of AUC0-24 with rifampin administration was 1.09 (90 % CI 0.9-1.33), suggesting that rifampin had a low impact during the initial phases of cabazitaxel elimination. Safety findings were consistent with previous results. CONCLUSIONS: Cabazitaxel pharmacokinetics are modified by drugs strongly affecting CYP3A. Co-administration of cabazitaxel with strong CYP3A inhibitors or inducers should be avoided.

Whole genome sequencing of glioblastoma multiforme identifies multiple structural variations involved in EGFR activation.

Next generation sequencing has become a powerful tool in dissecting and identifying mutations and genomic structural variants that accompany tumourigenesis. Sequence analysis of glioblastoma multiforme (GBM) illustrates the ability to rapidly identify mutations that may affect phenotype. Approximately 50% of human GBMs overexpress epidermal growth factor receptor (EGFR) which renders the EGFR protein a compelling therapeutic target. In brain tumours, attempts to target EGFR as a cancer therapeutic, however, have achieved little or no benefit. The mechanisms that drive therapeutic resistance to EGFR inhibitors in brain tumours are not well defined, and drug resistance contributes to the deadly and aggressive nature of the disease. Whole genome sequencing of four primary GBMs revealed multiple pathways by which EGFR protein abundance becomes deregulated in these tumours and will guide the development of new strategies for treating EGFR overexpressing tumours. Each of the four tumours displayed a different mechanism leading to increased EGFR protein levels. One mechanism is mediated by gene amplification and tandem duplication of the kinase domain. A second involves an intragenic deletion that generates a constitutively active form of the protein. A third combines the loss of a gene which encodes a protein that regulates EGFR abundance as well as an miRNA that modulates EGFR expression. A fourth mechanism entails loss of an ubiquitin ligase docking site in the C-terminal part of the protein whose absence inhibits turnover of the receptor.

The indoleamine 2,3-dioxygenase pathway controls complement-dependent enhancement of chemo-radiation therapy against murine glioblastoma.

BACKGROUND: Indoleamine 2,3-dioxygenase (IDO) is an enzyme with immune-suppressive properties that is commonly exploited by tumors to evade immune destruction. Anti-tumor T cell responses can be initiated in solid tumors, but are immediately suppressed by compensatory upregulation of immunological checkpoints, including IDO. In addition to these known effects on the adaptive immune system, we previously showed widespread, T cell-dependent complement deposition during allogeneic fetal rejection upon maternal treatment with IDO-blockade. We hypothesized that IDO protects glioblastoma from the full effects of chemo-radiation therapy by preventing vascular activation and complement-dependent tumor destruction. METHODS: To test this hypothesis, we utilized a syngeneic orthotopic glioblastoma model in which GL261 glioblastoma tumor cells were stereotactically implanted into the right frontal lobes of syngeneic mice. These mice were treated with IDO-blocking drugs in combination with chemotherapy and radiation therapy. RESULTS: Pharmacologic inhibition of IDO synergized with chemo-radiation therapy to prolong survival in mice bearing intracranial glioblastoma tumors. We now show that pharmacologic or genetic inhibition of IDO allowed chemo-radiation to trigger widespread complement deposition at sites of tumor growth. Chemotherapy treatment alone resulted in collections of perivascular leukocytes within tumors, but no complement deposition. Adding IDO-blockade led to upregulation of VCAM-1 on vascular endothelium within the tumor microenvironment, and further adding radiation in the presence of IDO-blockade led to widespread deposition of complement. Mice genetically deficient in complement component C3 lost all of the synergistic effects of IDO-blockade on chemo-radiation-induced survival. CONCLUSIONS: Together these findings identify a novel mechanistic link between IDO and complement, and implicate complement as a major downstream effector mechanism for the beneficial effect of IDO-blockade after chemo-radiation therapy. We speculate that this represents a fundamental pathway by which the tumor regulates intratumoral vascular activation and protects itself from immune-mediated tumor destruction.

Phosphatidylserine-selective targeting and anticancer effects of SapC-DOPS nanovesicles on brain tumors.

Brain tumors, either primary (e.g., glioblastoma multiforme) or secondary (metastatic), remain among the most intractable and fatal of all cancers. We have shown that nanovesicles consisting of Saposin C (SapC) and dioleylphosphatidylserine (DOPS) are able to effectively target and kill cancer cells both in vitro and in vivo. These actions are a consequence of the affinity of SapC-DOPS for phosphatidylserine, an acidic phospholipid abundantly present in the outer membrane of a variety of tumor cells and tumor-associated vasculature. In this study, we first characterize SapC-DOPS bioavailability and antitumor effects on human glioblastoma xenografts, and confirm SapC-DOPS specificity towards phosphatidylserine by showing that glioblastoma targeting is abrogated after in vivo exposure to lactadherin, which binds phosphatidylserine with high affinity. Second, we demonstrate that SapC-DOPS selectively targets brain metastases-forming cancer cells both in vitro, in co-cultures with human astrocytes, and in vivo, in mouse models of brain metastases derived from human breast or lung cancer cells. Third, we demonstrate that SapC-DOPS have cytotoxic activity against metastatic breast cancer cells in vitro, and prolong the survival of mice harboring brain metastases. Taken together, these results support the potential of SapC-DOPS for the diagnosis and therapy of primary and metastatic brain tumors.

Significant anti-tumor effect of bevacizumab in treatment of pineal gland glioblastoma multiforme.

Glioblastoma multiforme (GBM) is the most aggressive subtype of malignant gliomas. Current standard treatment for GBM involves a combination of cytoreduction through surgical resection, followed by radiation with concomitant and adjuvant chemotherapy (temozolomide). The role of bevacizumab in the treatment of GBM continues to be a topic of ongoing research and debate. Despite aggressive treatment, these tumors remain undoubtedly fatal, especially in the elderly. Furthermore, tumors present in the pineal gland are extremely rare, accounting for only 0.1-0.4 % of all adult brain tumors, with this location adding to the complexity of treatment. We present a case of GBM, at the rare location of pineal gland, in an elderly patient who was refractory to initial standard of care treatment with radiation and concomitant and adjuvant temozolomide, but who developed a significant response to anti-angiogenic therapy using bevacizumab.

A risk-adapted study of cisplatin and etoposide, with or without ifosfamide, in patients with metastatic seminoma: results of the GETUG S99 multicenter prospective study.

BACKGROUND: Whether patients with good prognosis and intermediate/poor prognosis advanced seminoma should be treated differently has not been defined. OBJECTIVE: To assess a risk-adapted chemotherapy regimen in patients with advanced seminoma. DESIGN, SETTING, AND PARTICIPANTS: A total of 132 patients were included in this prospective study. Patients with a good prognosis according to the International Germ Cell Cancer Collaboration Group (IGGCCG) were treated with four cycles of cisplatin-etoposide (EP). Patients with an intermediate prognosis according to the IGCCCG (or a poor prognosis according to the Medical Research Council classification) were treated with four cycles of VIP (EP and ifosfamide) and granulocyte colony-stimulating factor (G-CSF). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Survival curves were estimated using the Kaplan-Meier method. RESULTS AND LIMITATIONS: The median follow-up was 4.5 yr (range: 0.4-11.6 yr). Among 108 patients (82%) with a good prognosis who received EP, grade 3-4 toxicity included neutropenia (47%) and neutropenic fever (12%). Among the 24 patients (18%) with an intermediate/poor prognosis who received VIP plus G-CSF, toxicity included grade 3-4 neutropenia (36%), neutropenic fever (23%), thrombocytopenia (23%), anemia (23%), and a toxicity-related death (n=1; 4%). The 3-yr progression-free survival (PFS) rate was 93% (range: 85-97%) in the good prognosis group and 83% (range: 63-93%) in the intermediate/poor prognosis group (p=0.03 for PFS). The 3-yr overall survival (OS) rate was 99% (range: 92-100%) and 87% (range: 67-95%), respectively (p<0.005 for OS). Only four patients died of seminoma or its treatment. CONCLUSIONS: A risk-adapted chemotherapy policy for advanced seminoma yielded an excellent outcome with a 3-yr OS rate of 96%.