Ferry A.L.M. Eskens

Phase I dose-escalation and -expansion study of buparlisib (BKM120), an oral pan-Class I PI3K inhibitor, in patients with advanced solid tumors

SummaryPurpose The pan-Class I PI3K inhibitor buparlisib (BKM120) has shown activity in a range of preclinical cancer models. This first-in-man study was initiated to identify the maximum tolerated dose (MTD) of buparlisib (100xa0mg/day) and to assess safety and preliminary efficacy. Methods Patients with advanced solid tumors (Nu2009=u200983) enrolled in a Phase I dose-escalation and -expansion study of single-agent buparlisib. Patients in the dose-expansion arm (nu2009=u200943) had tumor samples with PIK3CA and/or PTEN alterations. Results The most common cancers were colorectal (nu2009=u200931) and breast cancer (nu2009=u200921). Median number of prior antineoplastic regimens was four (range: 1–12). Grade 3/4 adverse events (AEs) included asthenia (12.0xa0%) and performance status decrease (9.6xa0%). Treatment-related AEs (all grades) included decreased appetite, diarrhea, nausea (each in 33xa0% of patients), hyperglycemia (31xa0%) and rash (29xa0%). One confirmed partial response (PR; triple-negative breast cancer) and three unconfirmed PRs (parotid gland carcinoma, epithelioid hemangiothelioma, ER + breast cancer) were reported. Tumor molecular status did not predict clinical benefit in the full study cohort, or among the colorectal or breast cancer subpopulations. Pharmacodynamic biomarkers (18F-FDG-PET, C-peptide, pS6) demonstrated dose-dependent changes; however, tumor heterogeneity precluded a clear correlation with clinical benefit. Conclusion Buparlisib was well tolerated up to the 100xa0mg/day dose and showed preliminary activity in patients with advanced cancers. Future studies in more homogeneous patient populations will evaluate buparlisib in combination with other agents and further investigate the use of predictive biomarkers.

Mapatumumab, a Fully Human Agonistic Monoclonal Antibody That Targets TRAIL-R1, in Combination with Gemcitabine and Cisplatin: a Phase I Study

Purpose: To evaluate the safety, tolerability, pharmacokinetics, and antitumor activity of mapatumumab, a fully human monoclonal antibody targeting tumor necrosis factor–related apoptosis–inducing ligand receptor 1 (TRAIL-R1), in combination with gemcitabine and cisplatin. Experimental Design: Patients with advanced solid tumors received gemcitabine 1,250 mg/m2 i.v. on days 1 and 8 and cisplatin 80 mg/m2 i.v. on day 1 of each 21-day cycle. Escalating mapatumumab doses were administered i.v. every 21 days. Toxicity was evaluated and pharmacokinetic analysis of plasma mapatumumab, gemcitabine, 2-difluoro-2-deoxyuridine, and unbound and total platinum was done. TRAIL-R1 tumor expression was determined immunohistochemically. Results: Forty-nine patients received mapatumumab (1 mg/kg, n = 4; 3 mg/kg, n = 7; 10 mg/kg, n = 12; 20 mg/kg, n = 13; or 30 mg/kg, n = 13). A median of six cycles (range, 1-48) was administered. The adverse events most commonly observed reflect the toxicity profile of gemcitabine and cisplatin. Dose-limiting toxicities were seen in 3 of 12 patients at 10 mg/kg, consisting of grade 3 transaminitis, neutropenic fever, and grade 4 thrombocytopenia. At 20 mg/kg, 2 of 12 patients had dose-limiting toxicities, including grade 4 thrombocytopenia and grade 4 fatigue. The maximum tolerated dose was not reached. Pharmacokinetic interactions have not been observed. Twelve patients had a partial response, and 25 patients showed stable disease with a median duration of 6 months. Conclusions: Mapatumumab in combination with gemcitabine and cisplatin is safe and well tolerated at doses up to 30 mg/kg. Further studies on this combination are warranted. (Clin Cancer Res 2009;15(17):5584–90)

Phase I Pharmacokinetic and Pharmacodynamic Study of the First-in-Class Spliceosome Inhibitor E7107 in Patients with Advanced Solid Tumors

Purpose: To assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and clinical activity of E7107 administered as 5-minute bolus infusions on days 1, 8, and 15 in a 28-day schedule. Experimental Design: Patients with solid tumors refractory to standard therapies or with no standard treatment available were enrolled. Dose levels of 0.6 to 4.5 mg/m2 were explored. Results: Forty patients [24M/16F, median age 61 years (45–79)] were enrolled. At 4.5 mg/m2, dose-limiting toxicity (DLT) consisted of grade 3 diarrhea, nausea, and vomiting and grade 4 diarrhea, respectively, in two patients. At 4.0 mg/m2, DLT (grade 3 nausea, vomiting, and abdominal cramps) was observed in one patient. Frequently occurring side effects were mainly gastrointestinal. After drug discontinuation at 4.0 mg/m2, one patient experienced reversible grade 4 blurred vision. The maximum tolerated dose (MTD) is 4.0 mg/m2. No complete or partial responses during treatment were observed; one patient at 4.0 mg/m2 had a confirmed partial response after drug discontinuation. Pharmacokinetic analysis revealed a large volume of distribution, high systemic clearance, and a plasma elimination half-life of 5.3 to 15.1 hours. Overall drug exposure increased in a dose-dependent manner. At the MTD, mRNA levels of selected target genes monitored in peripheral blood mononuclear cells showed a reversible 15- to 25-fold decrease, whereas unspliced pre-mRNA levels of DNAJB1 and EIF4A1 showed a reversible 10- to 25-fold increase. Conclusion: The MTD for E7107 using this schedule is 4.0 mg/m2. Pharmacokinetics is dose-dependent and reproducible within patients. Pharmacodynamic analysis revealed dose-dependent reversible inhibition of pre-mRNA processing of target genes, confirming proof-of-principle activity of E7107. Clin Cancer Res; 19(22); 6296–304. ©2013 AACR.

A phase II open-label study of DHA-paclitaxel (Taxoprexin) by 2-h intravenous infusion in previously untreated patients with locally advanced or metastatic gastric or oesophageal adenocarcinoma

PurposeCombination chemotherapy regimens can improve survival in patients with advanced gastric and oesophageal adenocarcinoma. Docosahexaenoic acid (DHA)-paclitaxel is a novel conjugate formed by the covalent linkage of the fatty acid DHA to paclitaxel and may result in increased tumour exposure to paclitaxel without increased toxicity.Patients and methodsIn this single arm, phase II study of DHA-paclitaxel, eligible patients with previously untreated, inoperable locally advanced or metastatic adenocarcinoma of the oesophagus, oesophago-gastric junction or stomach were treated with DHA-paclitaxel (1,100xa0mg/m2) administered by 2-h intravenous infusion every 21 days.ResultsFifty-four patients were recruited of whom 53 were evaluable for toxicity, and 48 for response. There were five confirmed partial responses (9.4%) by the RECIST criteria. The median duration of response was 87 days (range 49–97 days), the median time to progression was 84 days (95% CI 78–124 days), and median overall survival was 262 days (95% CI 205–357 days). Grade ≥3 neutropaenia occurred in 93% of patients, and febrile neutropaenia in 17% of patients.ConclusionsDHA-paclitaxel has modest activity in patients with oesophago-gastric cancer and with haematological toxicity that is comparable to paclitaxel and docetaxel.

Phase I Dose Escalation Study of Telatinib, a Tyrosine Kinase Inhibitor of Vascular Endothelial Growth Factor Receptor 2 and 3, Platelet-Derived Growth Factor Receptor {beta}, and c-Kit, in Patients With Advanced or Metastatic Solid Tumors

PURPOSEnTelatinib (BAY 57-9352) is an orally available tyrosine kinase inhibitor of vascular endothelial growth factor receptor (VEGFR) -2, VEGFR-3, platelet-derived growth factor receptor-beta, and c-Kit. This phase I dose escalation study was conducted to evaluate the safety and tolerability of telatinib, with additional pharmacokinetic, pharmacodynamic, and efficacy assessments.nnnPATIENTS AND METHODSnPatients with solid tumors refractory to standard therapies or with no standard therapy available were enrolled. Doses of continuously administered telatinib were escalated from 20 mg once daily to 1,500 mg twice daily.nnnRESULTSnFifty-three patients were enrolled. Most frequently observed drug-related adverse events were nausea (26.4%; grade >or= 3, 0%) and hypertension (20.8%; grade 3, 11.3%; grade 4, 0%). Two dose-limiting toxicities were observed: one poorly controlled hypertension (600 mg twice daily), and one grade 2 weight loss, anorexia, and fatigue (1,500 mg twice daily). A formal maximum-tolerated dose was not reached. Telatinib was rapidly absorbed, with median time to peak concentration (t(max)) lower than 3 hours after dose. A nearly dose-proportional increase in exposure was observed with substantial variability. Telatinib half-life averaged 5.5 hours. Biomarker analyses showed dose-dependent increase in VEGF levels and decrease in plasma soluble VEGFR-2 levels, with a plateau at 900 mg twice daily. A decrease in tumor blood flow (K(trans) and IAUC(60)) was observed with dynamic contrast-enhanced magnetic resonance imaging. Best tumor response was stable disease, observed in 50.9% of patients.nnnCONCLUSIONnTelatinib was safe and well tolerated up to 1,500 mg twice daily. Based on pharmacodynamic and pharmacokinetic end points, telatinib 900 mg twice daily is the recommended dose for subsequent phase II studies.

Clinical trial design for target specific anticancer agents.

Recently a large number of new anticancer agents targeting specifically one or more of the extracellular, transmembrane, or intracellular (but extranuclear) processes involved in malignant transformation of cells or carcinogenesis have been developed. These agents show target specificity, predominantly resulting in growth inhibition in tumor models and less frequently in tumor regression, acting in a cytostatic rather than a cytotoxic way. In addition, based on their specific mechanism of action, these target specific agents are expected to have a more favorable toxicity profile. In exploring new anticancer agents, phase I studies generally focus on toxicity and are primarily designed to describe dose limiting toxicity and to determine the maximum tolerated dose and the dose recommended for phase II studies. These phase II studies are subsequently performed in small groups of patients using the percentage tumor regression to screen for anticancer efficacy. Due to the anticipated low toxicity profile and the mainly growth inhibiting activity of target specific agents, the design of phase I and II studies involving these agents will have to be adapted in several ways. It is emphasized that, although it is helpful to distinguish cytotoxic from cytostatic anticancer agents, this dichotomy can be a simplification. In this paper, we will discuss important issues that will have to be faced when developing clinical trials with these agents and we will specifically translate this into the already known concepts of trial design exploring cytotoxic and cytostatic agents.

A phase I and pharmacokinetic study of weekly paclitaxel and carboplatin in patients with metastatic esophageal cancer

Purpose: To determine the maximum-tolerated dose, toxicity profile, and pharmacokinetics of a fixed dose of paclitaxel followed by increasing doses of carboplatin, given weekly to patients with advanced esophageal or gastric junction cancer. Experimental Design: Paclitaxel was administered on day 1 as a 1-h infusion at a fixed dose of 100 mg/m2 followed by a 1-h infusion of carboplatin targeting an area under the curve (AUC) of 2–5 mg × min/ml, with cycles repeated on days 8, 15, 29, 36, and 43. Results: Forty patients [36 males; median (range) age, 57 (40–74) years] were enrolled. Dose-limiting toxicity was observed at a carboplatin AUC of 5 mg × min/ml and consisted of treatment delay attributable to myelosuppression. No grade 3/4 treatment-related nonhematological toxicity was observed. The highest dose intensity (>95% of the planned dose over time) was achieved with a carboplatin AUC of 4 mg × min/ml. The mean (±SD) AUCs of unbound (Cu) and total paclitaxel were 0.662 ± 0.186 and 7.37 ± 1.33 μm × h, respectively. Clearance of Cu was 188 ± 44.6 liter/h/m2, which is not significantly different from historical data (P = 0.52). Cremophor EL clearance was 123 ± 23 ml/h/m2, similar to previous findings. Of 37 patients evaluable for response, 1 had complete response, 19 had partial response, and 10 had stable disease, accounting for an overall response rate of 54%. Conclusions: This regimen is very tolerable and effective, and the recommended doses for additional studies are paclitaxel (100 mg/m2), with carboplatin targeting an AUC of 4 mg × min/ml.

A Phase Ib Dose-Escalation Study of Encorafenib and Cetuximab with or without Alpelisib in Metastatic BRAF-Mutant Colorectal Cancer

Preclinical evidence suggests that concomitant BRAF and EGFR inhibition leads to sustained suppression of MAPK signaling and suppressed tumor growth in BRAFV600E colorectal cancer models. Patients with refractory BRAFV600-mutant metastatic CRC (mCRC) were treated with a selective RAF kinase inhibitor (encorafenib) plus a monoclonal antibody targeting EGFR (cetuximab), with (n = 28) or without (n = 26) a PI3Kα inhibitor (alpelisib). The primary objective was to determine the maximum tolerated dose (MTD) or a recommended phase II dose. Dose-limiting toxicities were reported in 3 patients receiving dual treatment and 2 patients receiving triple treatment. The MTD was not reached for either group and the phase II doses were selected as 200 mg encorafenib (both groups) and 300 mg alpelisib. Combinations of cetuximab and encorafenib showed promising clinical activity and tolerability in patients with BRAF-mutant mCRC; confirmed overall response rates of 19% and 18% were observed and median progression-free survival was 3.7 and 4.2 months for the dual- and triple-therapy groups, respectively.Significance: Herein, we demonstrate that dual- (encorafenib plus cetuximab) and triple- (encorafenib plus cetuximab and alpelisib) combination treatments are tolerable and provide promising clinical activity in the difficult-to-treat patient population with BRAF-mutant mCRC. Cancer Discov; 7(6); 610-9. ©2017 AACR.See related commentary by Sundar et al., p. 558This article is highlighted in the In This Issue feature, p. 539.

The c-Met Tyrosine Kinase Inhibitor JNJ-38877605 Causes Renal Toxicity through Species-Specific Insoluble Metabolite Formation

Purpose: The receptor tyrosine kinase c-Met plays an important role in tumorigenesis and is a novel target for anticancer treatment. This phase I, first-in-human trial, explored safety, pharmacokinetics, pharmacodynamics, and initial antitumor activity of JNJ-38877605, a potent and selective c-Met inhibitor. Experimental Design: We performed a phase I dose-escalation study according to the standard 3+3 design. Results: Even at subtherapeutic doses, mild though recurrent renal toxicity was observed in virtually all patients. Renal toxicity had not been observed in preclinical studies in rats and dogs. Additional preclinical studies pointed toward the rabbit as a suitable toxicology model, as the formation of the M10 metabolite of JNJ-38877605 specifically occurred in rabbits and humans. Additional toxicology studies in rabbits clearly demonstrated that JNJ-38877605 induced species-specific renal toxicity. Histopathological evaluation in rabbits revealed renal crystal formation with degenerative and inflammatory changes. Identification of the components of these renal crystals revealed M1/3 and M5/6 metabolites. Accordingly, it was found that humans and rabbits showed significantly increased systemic exposure to these metabolites relative to other species. These main culprit insoluble metabolites were generated by aldehyde oxidase activity. Alternative dosing schedules of JNJ-3877605 and concomitant probenecid administration in rabbits failed to prevent renal toxicity at dose levels that could be pharmacologically active. Conclusions: Combined clinical and correlative preclinical studies suggest that renal toxicity of JNJ-38877605 is caused by the formation of species-specific insoluble metabolites. These observations preclude further clinical development of JNJ-38877605. Clin Cancer Res; 21(10); 2297–304. ©2015 AACR.

A phase I pharmacokinetic study of the vascular disrupting agent ombrabulin (AVE8062) and docetaxel in advanced solid tumours

Background:The vascular disrupting agent ombrabulin shows synergy with docetaxel in vivo. Recommended phase II doses were determined in a dose escalation study in advanced solid tumours.Methods:Ombrabulin (30-min infusion, day 1) followed by docetaxel (1-h infusion, day 2) every 3 weeks was explored. Ombrabulin was escalated from 11.5 to 42u2009mgu2009m−2 with 75u2009mgu2009m−2 docetaxel, then from 30 to 35u2009mgu2009m−2 with 100u2009mgu2009m−2 docetaxel. Recommended phase II dose cohorts were expanded.Results:Fifty-eight patients were treated. Recommended phase II doses were 35u2009mgu2009m−2 ombrabulin with 75u2009mgu2009m−2 docetaxel (35/75u2009mgu2009m−2; 13 patients) and 30u2009mgu2009m−2 ombrabulin with 100u2009mgu2009m−2 docetaxel (30/100u2009mgu2009m−2; 16 patients). Dose-limiting toxicities were grade 3 fatigue (two patients; 42/75, 35/100), grade 3 neutropaenic infection (25/75), grade 3 headache (42/75), grade 4 febrile neutropaenia (30/100), and grade 3 thrombosis (35/100). Toxicities were consistent with each agent; mild nausea/vomiting, asthaenia/fatigue, alopecia, and anaemia were common, as were neutropaenia and leukopaenia. Diarrhoea, nail disorders and neurological symptoms were frequent at 100u2009mgu2009m−2 docetaxel. Pharmacokinetic analyses did not show any relevant drug interactions. Ten patients had partial responses (seven at 30u2009mgu2009m−2 ombrabulin), eight lasting >3 months.Conclusions:Sequential administration of ombrabulin with 75 or 100u2009mgu2009m−2 docetaxel every 3 weeks is feasible.