Selection of Protein Kinase Inhibitors Based on Tumor Tissue Kinase Activity Profiles in Patients with Refractory Solid Malignancies: An Interventional Molecular Profiling Study.

LESSONS LEARNED: Clinically applicable tools are needed for treatment selection and repurposing of available protein kinase inhibitors (PKIs) in patients with advanced solid tumors refractory to standard treatment.Using a tyrosine kinase peptide substrate microarray, observed inhibitory activity in vitro could not sufficiently predict clinical benefit of treatment with the selected PKI. BACKGROUND: This exploratory molecular profiling study determined the feasibility and benefit of the selection of protein kinase inhibitors (PKIs) based on kinase activity profiling in patients with refractory solid malignancies. METHODS: Adult patients with biopsy-accessible refractory solid tumors were eligible. Per patient, the inhibitory potency of sunitinib, dasatinib, erlotinib, sorafenib, everolimus, and lapatinib was determined in tumor lysates from fresh biopsies using a tyrosine kinase peptide substrate microarray. The most active PKI in this in vitro assay was selected for treatment. RESULTS: Thirteen patients were enrolled in the feasibility part and underwent tumor biopsy. Of 12 patients in whom kinase activity profiling was performed, 11 started treatment with a selected PKI: dasatinib in 8, sunitinib in 2, and erlotinib in 1 patient(s). Eight patients were evaluable for response. One patient had stable disease (SD) >4 months on sunitinib; one patient had SD at 6 weeks but progressive disease (PD) at 12 weeks. The remaining patients had PD after 6 weeks of treatment. CONCLUSION: Kinase inhibition profiles of multiple PKIs can be reliably determined using fresh tumor biopsies from patients with refractory solid tumors. However, the current in vitro microarray selection approach insufficiently predicted clinical benefit of PKI treatment in these patients.

Phase I Dose-Escalation Study of Once Weekly or Once Every Two Weeks Administration of High-Dose Sunitinib in Patients With Refractory Solid Tumors.

PURPOSE: Dose and schedule optimization of treatment with tyrosine kinase inhibitors is of utmost importance. On the basis of preclinical data, a phase I clinical trial of once weekly or once every 2 weeks administration of high-dose sunitinib in patients with refractory solid malignancies was conducted. PATIENTS AND METHODS: Patients with advanced cancer refractory to standard treatment were eligible. With use of a standard 3 + 3 phase I design, patients received escalating doses of sunitinib, in 100 mg increments, starting at 200 mg once weekly. In both the once weekly and once every 2 weeks cohorts, 10 more patients were included at the maximum tolerated dose level. Primary end points were safety and tolerability. RESULTS: Sixty-nine patients with advanced cancer, predominantly colorectal cancer (42%), were treated with this alternative dosing regimen. Maximum tolerated dose was established at 300 mg once weekly and 700 mg once every 2 weeks, resulting in nine- and 18-fold higher maximum plasma concentrations compared with standard dose, respectively. Treatment was well tolerated, with fatigue (81%), nausea (48%), and anorexia (33%) being the most frequent adverse events. The only grade 3 or 4 treatment-related adverse event in 5% or more of patients was fatigue (6%). Sixty-three percent of patients had significant clinical benefit, with a 30% progression-free survival of 5 months or more. CONCLUSION: Sunitinib administered once weekly at 300 mg or once every 2 weeks at 700 mg is feasible, with comparable tolerability as daily administration. Administration of 700 mg once every 2 weeks can be considered as the most optimal schedule because of the highest maximum plasma concentration being reached. The promising preliminary antitumor activity of this alternative schedule in heavily pretreated patients warrants further clinical evaluation and might ultimately indicate a class characteristic of tyrosine kinase inhibitors.

Dose-finding study of the multitargeted tyrosine kinase inhibitor SU6668 in patients with advanced malignancies.

PURPOSE: SU6668 is a tyrosine kinase inhibitor which targets platelet-derived growth factor receptor-beta, fibroblast growth factor receptor-1, vascular endothelial growth factor receptor-2, and KIT. We did a phase I study to define the maximum tolerated dose and to assess the pharmacokinetics of SU6668 administered orally thrice daily with food. PATIENTS AND METHODS: Patients with histologically proven, advanced, and progressive solid tumors were included at a starting dose level of 400 mg/m2 thrice daily. The early onset of dose-limiting toxicities (DLT) required dose reductions to 100 and 200 mg/m2 thrice daily. Pharmacokinetics was done on days 1, 28, and 56. RESULTS: Sixteen patients were included. Two of the first three patients developed DLTs, which consisted of grade 4 fatigue and grade 3 serositis-like pains. Six patients at dose level 100 mg/m2 thrice daily experienced no DLT. At dose level 200 mg/m2 thrice daily, two out of seven patients experienced DLTs consisting of grade 3 abdominal pain, grade 4 anorexia and grade 3 nausea/vomiting. Increasing doses resulted in a disproportional increase in area under the curve and C(max) (peak plasma concentration). Both variables, however, decreased significantly on days 28 and 56 compared with day 1 (P < 0.05). No objective responses were observed. Acute phase response, probably mediated by interleukin-6, was observed in serial blood samples. CONCLUSIONS: The maximum tolerated dose of SU6668 given orally, thrice daily under fed conditions, is 100 mg/m2. Because of the low plasma levels reached at this dose level, the efficacy of SU6668 as a single agent is not to be expected.

Dose-finding and pharmacokinetic study of cisplatin, gemcitabine, and SU5416 in patients with solid tumors.

PURPOSE: To investigate the feasibility and pharmacokinetics of the combination cisplatin, gemcitabine, and SU5416. PATIENTS AND METHODS: Patients received cisplatin 80 mg/m(2) on day 1, gemcitabine 1,250 mg/m(2) on days 1 and 8, repeated every 3 weeks, and SU5416 (85 and 145 mg/m(2)) intravenously twice weekly. Pharmacokinetics of all three agents, side effects, and antitumor response were investigated in patients with solid tumors amenable to therapy with cisplatin/gemcitabine. RESULTS: In the first cohort of three patients entered at the 85 mg/m(2) dose, no dose-limiting toxicities were observed. In the next cohort (145 mg/m(2)), three patients developed a thromboembolic event. After entry was restricted to patients with low thromboembolic risk, three additional patients enrolled at 145 mg/m(2) developed a thromboembolic event. The dose was then reduced to 85 mg/m(2) in all patients still on the study, and three additional patients were entered on this dose level. In 19 treated patients, eight patients developed nine thromboembolic events (three transient ischemic attacks, two cerebrovascular accidents, and four deep venous thromboses). The most common toxicities observed were those previously reported for SU5416 alone (headache and phlebitis) and for this chemotherapy regimen (nausea, thrombocytopenia, and leucopenia). No significant pharmacologic interaction among the three drugs was observed. Response rates were similar to those expected in the patient population selected for this study. Analysis of variables of the coagulation cascade and of vessel wall activation was performed in three patients and showed significant increases in thrombin generation and endothelial cell perturbation in a treatment cycle-dependent manner. CONCLUSION: The incidence of thromboembolic events, possibly related to the particular regimen tested in this study, discourages further investigation of this regimen.

A phase I study of the natural killer T-cell ligand alpha-galactosylceramide (KRN7000) in patients with solid tumors.

PURPOSE: alpha-galactosylceramide (KRN7000) is a glycosphingolipid that has been shown to inhibit tumor growth and to prolong survival in inoculated mice through activation of natural killer (NK) T cells. We performed a dose escalation study of KRN7000 in advanced cancer patients. EXPERIMENTAL DESIGN: Patients with solid tumors received i.v. KRN7000 (50-4,800 micro g/m(2)) on days 1, 8, and 15 of a 4-weekly cycle. Patients were given 1 cycle and, in the absence of dose-limiting toxicity or progression, treatment was continued. Pharmacokinetics (PK) and immunomonitoring were performed in all patients. RESULTS: Twenty-four patients were entered into this study. No dose-limiting toxicity was observed over a wide range of doses (50-4,800 micro g/m(2)). PK was linear in the dose range tested. Immunomonitoring demonstrated that NKT cells (CD3+Valpha24+Vbeta11+) typically disappeared from the blood within 24 h of KRN7000 injection. Additional biological effects included increased serum cytokine levels (tumor necrosis factor alpha and granulocyte macrophage colony-stimulating factor) in 5 of 24 patients and a transient decrease in peripheral blood NK cell numbers and cytotoxicity in 7 of 24 patients. Importantly, the observed biological effects depended on pretreatment NKT-cell numbers rather than on the dose of KRN7000. Pretreatment NKT-cell numbers were significantly lower in patients compared with healthy controls (P = 0.0001). No clinical responses were recorded and seven patients experienced stable disease for a median duration of 123 days. CONCLUSION: i.v. KRN7000 is well tolerated in cancer patients over a wide range of doses. Biological effects were observed in several patients with relatively high pretreatment NKT-cell numbers. Other therapeutic strategies aiming at reconstitution of the deficient NKT-cell population in cancer patients may be warranted.

Pharmacokinetics and preliminary clinical data of the novel chemoprotectant BNP7787 and cisplatin and their metabolites.

INTRODUCTION: BNP7787 (disodium 2,2'-dithio-bis-ethane sulfonate) is currently undergoing development as a chemoprotective agent to prevent common and serious cisplatin-induced side effects. In the kidneys, intestine, and liver, BNP7787 is believed to undergo intracellular conversion into 2-mercaptoethane sulfonate (mesna), which can locally inactivate toxic platinum species. Methods and objectives In a phase I trial, 25 patients with advanced solid tumors received a 1-hour intravenous infusion of 75 mg/m(2) cisplatin immediately preceded by a 15-minute intravenous infusion of BNP7787 every 3 weeks. For pharmacokinetic investigation of BNP7787 and mesna and a possible mutual pharmacokinetic interaction between BNP7787 and cisplatin, cisplatin and BNP7787 were also administered as single agents in 14 of 25 patients. The dose of BNP7787 was escalated from 4.1 to 41 g/m(2). Patients were also monitored for tumor response and possible side effects from BNP7787. RESULTS: The maximum plasma concentration of mesna was reached approximately 1.7 hours after the start of the BNP7787 infusion. The maximum plasma concentration and area under the curve to infinity (AUC( infinity )) of BNP7787 and mesna increased linearly with the dose. The mean volume of distribution of BNP7787 (+/-SD) was approximately 0.26 +/- 0.08 L/kg. The mean normalized AUC( infinity ) of mesna was only approximately 8% of the normalized AUC( infinity ) of BNP7787. The pharmacokinetic profile of mesna was unaffected by cisplatin and its metabolites. None of the dose levels of BNP7787 (4.1-41 g/m(2)) administered appeared to influence the pharmacokinetic profile of total platinum, unbound platinum, or monohydrated cisplatin. The observed effects regarding a possible mutual interaction between BNP7787 and intact cisplatin were minor, and none were statistically significant at BNP7787 dose levels of 18.4 to 41 g/m(2). The confidence intervals for the pharmacokinetic parameters of BNP7787 and intact cisplatin, however, were relatively broad. Overall, BNP7787 was well tolerated at all dose levels (4.1-41.0 g/m(2)). The most frequently reported event related to BNP7787 was local intravenous site discomfort; the majority of events were mild (grade 1). Side effects of BNP7787 at the highest dose level of 41 g/m(2) were more prominent and included nausea and vomiting, as well as a warm feeling or flushing (grade 2 or lower). Partial tumor responses and stable disease were measured in 12 of 25 patients. CONCLUSION: BNP7787 was relatively nontoxic at doses up to 41 g/m(2). The combination of BNP7787 with cisplatin did not alter the pharmacokinetic profiles of mesna or the cisplatin metabolites. At the higher dose levels of BNP7787 (18.4 to 41 g/m(2)), there appeared to be no mutual interaction between BNP7787 and intact cisplatin, which needs to be confirmed in a larger number of patients. The absence of a mutual interaction between BNP7787 and intact cisplatin is consistent with the observation that several patients had objective tumor responses with BNP7787 and cisplatin administration.

A phase I pharmacologic study of necitumumab (IMC-11F8), a fully human IgG1 monoclonal antibody directed against EGFR in patients with advanced solid malignancies.

PURPOSE: This study aimed to determine a maximum tolerated dose (MTD) and recommended dose for disease-directed studies of necitumumab (IMC-11F8), a fully human IgG(1) monoclonal antibody directed at the epidermal growth factor receptor, and to characterize the safety profile, pharmacokinetics, preliminary antitumor activity, and immunogenicity of necitumumab. EXPERIMENTAL DESIGN: Patients with advanced solid malignancies were treated with 100 to 1,000 mg (flat dosing) necitumumab followed by a 2-week pharmacokinetics sampling period, before beginning 6-week cycles of therapy. RESULTS: Sixty patients received necitumumab weekly (29 patients) or every other week (31 patients). Two patients receiving 1,000 mg every 2 weeks experienced dose-limiting toxicities (DLT; grade 3 headache), accompanied by grade 3 nausea and vomiting in one patient. Occurring hours after the initial dose, these DLTs established 800 mg as the MTD. Mild dose-related skin toxicity was the most common drug-related toxicity (80%). One patient in each arm experienced grade 3 acneform rash, which responded to oral antibiotics and topical therapy. Toxicity was similar on both schedules. Necitumumab exhibited saturable elimination and nonlinear pharmacokinetics. At 800 mg (both arms), its half-life was approximately 7 days. All patients treated with >or=600 mg necitumumab achieved target trough concentrations (>or=40 microg/mL). Antibodies against necitumumab were not detected. Partial response and stable disease were experienced by 2 and 16 patients, respectively. CONCLUSION: Well tolerated, necitumumab is associated with preliminary evidence of antitumor activity, and achieves biologically relevant concentrations throughout the dosing period. The recommended dose of necitumumab for further clinical development is 800 mg (flat dose) weekly or every 2 weeks based on the clinical setting.

Imatinib mesylate in patients with WHO B3 thymomas and thymic carcinomas.

Thymic malignancies are rare tumors of the mediastinum. c-KIT is highly expressed in thymic carcinomas (TC) but infrequently in thymomas. Anecdotal experience suggests activity of imatinib mesylate in TC. Patients with unresectable World Health Organization B3 thymomas or TC, performance status 0 to 2, good organ function, and measurable disease were enrolled in this study. Imatinib was administered at 600 mg PO daily. Seven patients were recruited at one institution: two World Health Organization B3 thymomas and five TC. Imatinib treatment was generally well tolerated. Two patients had stable disease and five progressed. Median survival was 4 months, and median time to progression was 2 months. c-KIT expression was found in one of four samples by immunohistochemistry. No mutations were detected in the c-KIT or PDGFRA genes in three samples analyzed. Imatinib has no major activity in this rare tumor. Given the small number of patients treated in this study, selection based on presence of c-KIT mutations might be warranted.