James P. Stevenson

Mechanisms of Hypertension Associated With BAY 43-9006

PURPOSE BAY 43-9006 (sorafenib) is an inhibitor of Raf kinase, the vascular endothelial growth factor (VEGF) receptor-2, and angiogenesis in tumor xenografts. The current study investigated the incidence, severity, and mechanism of blood pressure (BP) elevation in patients treated with BAY 43-9006. PATIENTS AND METHODS Twenty patients received BAY 43-9006 400 mg orally twice daily. BP and heart rate were measured at baseline and then every 3 weeks for 18 weeks. VEGF, catecholamines, endothelin I, urotensin II, renin, and aldosterone were measured at baseline and after 3 weeks of therapy. We assessed vascular stiffness at baseline, after 3 to 6 weeks of therapy, and again after 9 to 10 months of therapy. RESULTS Fifteen (75%) of 20 patients experienced an increase of > or = 10 mmHg in systolic BP (SBP), and 12 (60%) of 20 patients experienced an increase of > or = 20 mmHg in SBP compared with their baseline value, with a mean change of 20.6 mmHg (P < .0001) after 3 weeks of therapy. There were no statistically significant changes in humoral factors, although there was a statistically significant inverse relationship between decreases in catecholamines and increases in SBP, suggesting a secondary response to BP elevation. Measures of vascular stiffness increased significantly during the period of observation. CONCLUSION Treatment with BAY 43-9006 is associated with a significant and sustained increase in BP. The lack of significant change in circulating factors suggests that these humoral factors had little role in the increase in BP.

Phase I Trial of the Antivascular Agent Combretastatin A4 Phosphate on a 5-Day Schedule to Patients With Cancer: Magnetic Resonance Imaging Evidence for Altered Tumor Blood Flow

PURPOSE Combretastatin A4 (CA4) phosphate (CA4P) inhibits microtubule polymerization and is toxic to proliferating endothelial cells in vitro. It causes reversible vascular shutdown in established tumors in vivo, consistent with an antivascular mechanism of action. The present study investigated escalating doses of CA4P administered intravenously to patients with advanced cancer. PATIENTS AND METHODS Patients with solid malignancies and good performance status received CA4P as a 10-minute infusion daily for 5 days repeated every 3 weeks. Pharmacokinetic sampling was performed during cycle 1. Patients receiving >/= 52 mg/m2/d had serial dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) studies to measure changes in tumor perfusion with CA4P treatment. RESULTS Thirty-seven patients received 133 treatment cycles. CA4P dose levels ranged from 6 mg/m2 to 75 mg/m2 daily. Severe pain at sites of known tumor was dose limiting at 75 mg/m2. Dose-limiting cardiopulmonary toxicity (syncope and dyspnea or hypoxia) was noted as well in two patients treated at 75 mg/m2. Other toxicities included hypotension, ataxia, dyspnea, nausea or vomiting, headache, and transient sensory neuropathy. Plasma CA4P and CA4 area under the concentration-time curve and maximal concentration values increased linearly with dose. Tumor perfusion, as measured by the first-order rate constant of gadolinium plasma to tissue transfer during DCE-MRI studies, was found to decrease in eight of 10 patients. Relationships were also demonstrated between perfusion changes and pharmacokinetic indices. A partial response was observed in a patient with metastatic soft tissue sarcoma, and 14 patients exhibited disease stability for a minimum of two cycles. CONCLUSION Doses of CA4P on a daily times five schedule of 52 to 65 mg/m2 were reasonably well-tolerated. The 52 mg/m2 dose is recommended for further study based on cumulative phase I experience with CA4P. Antitumor efficacy was observed, and the use of DCE-MRI provided a valuable noninvasive measure of the vascular effects of CA4P treatment.

Multicenter, Double-Blind, Placebo-Controlled, Randomized Phase II Trial of Gemcitabine/Cisplatin Plus Bevacizumab or Placebo in Patients With Malignant Mesothelioma

PURPOSE Gemcitabine plus cisplatin is active in malignant mesothelioma (MM), although single-arm phase II trials have reported variable outcomes. Vascular endothelial growth factor (VEGF) inhibitors have activity against MM in preclinical models. We added the anti-VEGF antibody bevacizumab to gemcitabine/cisplatin in a multicenter, double-blind, placebo-controlled randomized phase II trial in patients with previously untreated, unresectable MM. PATIENTS AND METHODS Eligible patients had an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1 and no thrombosis, bleeding, or major blood vessel invasion. The primary end point was progression-free survival (PFS). Patients were stratified by ECOG performance status (0 v 1) and histologic subtype (epithelial v other). Patients received gemcitabine 1,250 mg/m(2) on days 1 and 8 every 21 days, cisplatin 75 mg/m(2) every 21 days, and bevacizumab 15 mg/kg or placebo every 21 days for six cycles, and then bevacizumab or placebo every 21 days until progression. RESULTS One hundred fifteen patients were enrolled at 11 sites; 108 patients were evaluable. Median PFS time was 6.9 months for the bevacizumab arm and 6.0 months for the placebo arm (P = .88). Median overall survival (OS) times were 15.6 and 14.7 months in the bevacizumab and placebo arms, respectively (P = .91). Partial response rates were similar (24.5% for bevacizumab v 21.8% for placebo; P = .74). A higher pretreatment plasma VEGF concentration (n = 56) was associated with shorter PFS (P = .02) and OS (P = .0066), independent of treatment arm. There were no statistically significant differences in toxicity of grade 3 or greater. CONCLUSION The addition of bevacizumab to gemcitabine/cisplatin in this trial did not significantly improve PFS or OS in patients with advanced MM.

Clinical Pharmacokinetics and Administration of Established Platinum Drugs

We review the pharmacology and clinical administration of the commonly used platinum-based anticancer drugs cisplatin and carboplatin, and the more recently approved diamminocyclohexane-based oxaliplatin. The development of analogues of cisplatin has been focused upon identifying compounds with less toxicity and with a different spectrum of activity.Carboplatin exemplifies the former, while the initial data with oxaliplatin support its activity in cisplatin-resistant tumours. The clinical pharmacokinetics of the drugs are reviewed. Incorporation of these data into the design of clinical regimens has permitted individualised therapy with carboplatin, and has enhanced safety. Additional investigation of the pharmacodynamics of all of these agents is expected to result in their selective application. The clinical effects of these analogues are discussed.

Phase I Clinical/Pharmacokinetic and Pharmacodynamic Trial of the c-raf-1 Antisense Oligonucleotide ISIS 5132 (CGP 69846A)

PURPOSE Raf-1 is a protein kinase that plays a broad role in oncogenic signaling and acts as a downstream effector of Ras in the mitogen-activated protein kinase pathway. The present study was designed to determine the maximum-tolerated dose (MTD), toxicity profile, pharmacokinetics, and antitumor activity of the c-raf-1 antisense oligodeoxynucleotide ISIS 5132 (CGP 69846A; ISIS Pharmaceuticals Inc, Carlsbad, CA). The effect of ISIS 5132 on c-raf-1 gene expression in peripheral-blood mononuclear cells (PBMCs) of treated patients was studied using a reverse transcriptase polymerase chain reaction assay. PATIENTS AND METHODS Patients with refractory malignancies received ISIS 5132 as a 2-hour intravenous infusion three times weekly for 3 consecutive weeks. Pharmacokinetic sampling was performed during the first cycle in all patients; PBMCs for c-raf-1 mRNA analysis were collected at baseline and on days 3, 5, 8, and 15 of cycle 1 and on day 1 of each cycle thereafter. RESULTS Thirty-one patients received ISIS 5132 at one of nine dose levels ranging from 0.5 mg/kg to 6.0 mg/kg. Clinical toxicities included fever and fatigue, but these were not dose limiting. A clinically defined MTD was not reached. The harmonic mean half-life of ISIS 5132 was 59.8 minutes (range, 35.5 to 107.3 minutes). The area under the concentration-time curve increased linearly with dose, and mean plasma clearance was 1.86 mL/kg/min (range, 1.21 to 2.41 mL/kg/min). Two patients experienced prolonged stable disease lasting more than 7 months, which was associated with persistent reduction in c-raf-1 expression in PBMCs. Significant decreases in c-raf-1 expression were identified at time points after the baseline value (P <.05) at doses >/= 2.5 mg/kg. CONCLUSION ISIS 5132 is well tolerated at doses up to 6.0 mg/kg when administered as a thrice weekly 2-hour infusion for 3 consecutive weeks. The pharmacokinetic behavior of the drug is reproducible, and suppression of target gene expression is observed in circulating PBMCs.

Factors Affecting the Risk of Brain Metastases After Definitive Chemoradiation for Locally Advanced Non–Small-Cell Lung Carcinoma

PURPOSE As therapy for locally advanced non-small-cell lung carcinoma (NSCLC) improves, brain metastases (BM) may become a greater problem. We analyzed our chemoradiation experience for patients at highest risk for the brain as the first failure site. METHODS Records for 150 consecutive patients with stage II/III NSCLC treated definitively with chemoradiation from June 1992 to June 1998 at the University of Pennsylvania were reviewed. Most patients (89%) received cisplatin, paclitaxel, or both. All had negative brain imaging before treatment. Posttreatment brain imaging was performed for suspicious symptoms. Incidence of BM was examined as a function of age, sex, histology, stage, performance status, weight loss, tumor location, surgery, radiation dose, initial radiation field, chemotherapy regimen, and chemotherapy timing. RESULTS Crude and 2-year actuarial rates of BM were 19% and 30%, respectively. Among pretreatment parameters, stage IIIB was associated with a higher risk of BM (P <.04) versus stage II/IIIA. Histology alone was not significant (P <.12), although patients with IIIB nonsquamous tumors had an exceptionally high 2-year BM rate of 42% (P <.01 v all others). Examining treatment-related parameters, crude and 2-year actuarial risk of BM were 27% and 39%, respectively, in patients receiving chemotherapy before radiotherapy and 15% and 20%, respectively, when radiotherapy was not delayed (P <.05). On multivariate analysis, timing of chemotherapy (P <.01) and stage IIIA versus IIIB (P <.01) remained significant. CONCLUSION Patients with later stage, nonsquamous NSCLC, particularly those receiving induction chemotherapy, have sufficiently common BM rates to justify future trials including prophylactic cranial irradiation.

Identification of genes associated with platinum drug sensitivity and resistance in human ovarian cancer cells.

Platinum-based chemotherapeutic regimens are ultimately unsuccessful due to intrinsic or acquired drug resistance. Understanding the molecular basis for platinum drug sensitivity/resistance is necessary for the development of new drugs and therapeutic regimens. In an effort to identify such determinants, we evaluated the expression of approximately 4000 genes using cDNA microarray screening in a panel of 14 unrelated human ovarian cancer cell lines derived from patients who were either untreated or treated with platinum-based chemotherapy. These data were analysed relative to the sensitivities of the cells to four platinum drugs (cis-diamminedichloroplatinum (cisplatin), carboplatin, DACH-(oxalato)platinum (II) (oxaliplatin) and cis-diamminedichloro (2-methylpyridine) platinum (II) (AMD473)) as well as the proliferation rate of the cells. Correlation analysis of the microarray data with respect to drug sensitivity and resistance revealed a significant association of Stat1 expression with decreased sensitivity to cisplatin (r=0.65) and AMD473 (r=0.76). These results were confirmed by quantitative RT–PCR and Western blot analyses. To study the functional significance of these findings, the full-length Stat1 cDNA was transfected into drug-sensitive A2780 human ovarian cancer cells. The resulting clones that exhibited increased Stat1 expression were three- to five-fold resistant to cisplatin and AMD473 as compared to the parental cells. The effect of inhibiting Jak/Stat signalling on platinum drug sensitivity was investigated using the Janus kinase inhibitor, AG490. Pretreatment of platinum-resistant cells with AG490 resulted in significant increased sensitivity to AMD473, but not to cisplatin or oxaliplatin. Overall, the results indicate that cDNA microarray analysis may be used successfully to identify determinants of drug sensitivity/resistance and future functional studies of other candidate genes from this database may lead to an increased understanding of the drug resistance phenotype.

A phase I study of Foscan-mediated photodynamic therapy and surgery in patients with mesothelioma

BACKGROUND Photodynamic therapy (PDT) is a light-based cancer treatment that, in the correct setting, can be delivered intraoperatively as an adjuvant therapy. A phase I clinical trial combining surgical debulking with Foscan-mediated PDT was performed in patients with malignant pleural mesothelioma. The purpose of the study was to define the toxicities and to determine the maximally tolerated dose (MTD) of Foscan-mediated PDT. METHODS A total of 26 patients completed treatment. Tumor debulking was accomplished with either an extrapleural pneumonectomy (7 patients) or a lung-sparing pleurectomy-decortication (19 patients). Patients were injected with Foscan before surgery, and 652 nm light was delivered intraoperatively after completion of surgical debulking. Four light sensors were placed in the chest, allowing delivery of light to a uniform measured dose throughout the hemithorax. RESULTS Four dose levels were explored. The MTD was 0.1 mg/kg of Foscan injected 6 days before surgery in combination with 10 J x cm(-2) 652 nm light. Dose limiting toxicity at the next higher dose was a systemic capillary leak syndrome leading to death in 2 of 3 patients treated at that dose. Other PDT-related toxicities included wound burns and skin photosensitivity. In all, 14 patients were treated at the MTD without significant complications. CONCLUSIONS Foscan-mediated PDT can be safely combined with surgery at the established MTD. Unlike most other surgery-based multimodal treatments for mesothelioma, Foscan-mediated PDT affords the option, in selected patients, of accomplishing tumor debulking with a lung-sparing procedure rather than an extrapleural pneumonectomy. A phase II study is warranted.

Phase I trial of combretastatin A-4 phosphate with carboplatin

Purpose: Preclinical evidence of synergy led to a phase I trial employing combretastatin A-4 phosphate (CA4P), a novel tubulin-binding antivascular drug, in combination with carboplatin. Experimental Design: Based on preclinical scheduling studies, patients were treated on day 1 of a 21-day cycle. Carboplatin was given as a 30-minute i.v. infusion and CA4P was given 60 minutes later as a 10-minute infusion. Results: Sixteen patients with solid tumors received 40 cycles of therapy at CA4P doses of 27 and 36 mg/m2 together with carboplatin at area under the concentration-time curve (AUC) values of 4 and 5 mg min/mL. The dose-limiting toxicity of thrombocytopenia halted the dose escalation phase of the study. Four patients were treated at an amended dose level of CA4P of 36 mg/m2 and carboplatin AUC of 4 mg min/mL although grade 3 neutropenia and thrombocytopenia were still observed. Three lines of evidence are adduced to suggest that a pharmacokinetic interaction between the drugs results in greater thrombocytopenia than anticipated: the carboplatin exposure (as AUC) was greater than predicted; the platelet nadirs were lower than predicted; and the deviation of the carboplatin exposure from predicted was proportional to the AUC of CA4, the active metabolite of CA4P. Patient benefit included six patients with stable disease lasting at least four cycles. Conclusion: This study of CA4P and carboplatin given in combination showed dose-limiting thrombocytopenia. Pharmacokinetic/pharmacodynamic modeling permitted the inference that altered carboplatin pharmacokinetics caused the increment in platelet toxicity.

Radical pleurectomy and intraoperative photodynamic therapy for malignant pleural mesothelioma.

BACKGROUND Radical pleurectomy (RP) for mesothelioma is often considered either technically unfeasible or an operation limited to patients who would not tolerate a pneumonectomy. The purpose of this study was to review our experience using RP and intraoperative photodynamic therapy (PDT) for mesothelioma. METHODS Thirty-eight patients (42-81 years) underwent RP-PDT. Thirty five of 38 (92%) patients also received systemic therapy. Standard statistical techniques were used for analysis. RESULTS Thirty seven of 38 (97%) patients had stage III/IV cancer (according to the American Joint Committee on Cancer [AJCC manual 7th Edition, 2010]) and 7/38 (18%) patients had nonepithelial subtypes. Macroscopic complete resection was achieved in 37/38 (97%) patients. There was 1 postoperative mortality (stroke). At a median follow-up of 34.4 months, the median survival was 31.7 months for all 38 patients, 41.2 months for the 31/38 (82%) patients with epithelial subtypes, and 6.8 months for the 7/38 (18%) patients with nonepithelial subtypes. Median progression-free survival (PFS) was 9.6, 15.1, and 4.8 months, respectively. The median survival and PFS for the 20/31 (64%) patients with N2 epithelial disease were 31.7 and 15.1 months, respectively. CONCLUSIONS It was possible to achieve a macroscopic complete resection using lung-sparing surgery in 97% of these patients with stage III/IV disease. The survival we observed with this approach was unusually long for the patients with the epithelial subtype but, interestingly, the PFS was not. The reason for this prolonged survival despite recurrence is not clear but is potentially related to preservation of the lung or some PDT-induced effect, or both. We conclude that the results of this lung-sparing approach are safe, encouraging, and warrant further investigation.