Gordon C Jayson

Experimentally-derived functional form for a population-averaged high-temporal-resolution arterial input function for dynamic contrast-enhanced MRI

Rapid T1‐weighted 3D spoiled gradient‐echo (GRE) data sets were acquired in the abdomen of 23 cancer patients during a total of 113 separate visits to allow dynamic contrast‐enhanced MRI (DCE‐MRI) analysis of tumor microvasculature. The arterial input function (AIF) was measured in each patient at each visit using an automated AIF extraction method following a standardized bolus administration of gadodiamide. The AIFs for each patient were combined to obtain a mean AIF that is representative for any individual. The functional form of this general AIF may be useful for studies in which AIF measurements are not possible. Improvements in the reproducibility of DCE‐MRI model parameters (Ktrans, ve, and vp) were observed when this new, high‐temporal‐resolution population AIF was used, indicating the potential for increased sensitivity to therapy‐induced change. Magn Reson Med, 2006.

DCE-MRI biomarkers in the clinical evaluation of antiangiogenic and vascular disrupting agents

Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) is now frequently used in early clinical trial assessment of antiangiogenic and vascular disrupting compounds. Evidence of drug efficacy and dose-dependent response has been demonstrated with some angiogenesis inhibitors. This review highlights the critical issues that influence T1-weighted DCE-MRI data acquisition and analysis, identifies important areas for future development and reviews the clinical trial findings to date.

Early versus delayed treatment of relapsed ovarian cancer (MRC OV05/EORTC 55955): a randomised trial

BACKGROUND Serum CA125 concentration often rises several months before clinical or symptomatic relapse in women with ovarian cancer. In the MRC OV05/EORTC 55955 collaborative trial, we aimed to establish the benefits of early treatment on the basis of increased CA125 concentrations compared with delayed treatment on the basis of clinical recurrence. METHODS Women with ovarian cancer in complete remission after first-line platinum-based chemotherapy and a normal CA125 concentration were registered for this randomised controlled trial. Clinical examination and CA125 measurement were done every 3 months. Patients and investigators were masked to CA125 results, which were monitored by coordinating centres. If CA125 concentration exceeded twice the upper limit of normal, patients were randomly assigned (1:1) by minimisation to early or delayed chemotherapy. Patients and clinical sites were informed of allocation to early treatment, and treatment was started as soon as possible within 28 days of the increased CA125 measurement. Patients assigned to delayed treatment continued masked CA125 measurements, with treatment commencing at clinical or symptomatic relapse. All patients were treated according to standard local practice. The primary outcome was overall survival. Analysis was by intention to treat. This study is registered, ISRCTN87786644. FINDINGS 1442 patients were registered for the trial, of whom 529 were randomly assigned to treatment groups and were included in our analysis (265 early, 264 delayed). With a median follow-up of 56·9 months (IQR 37·4-81·8) from randomisation and 370 deaths (186 early, 184 delayed), there was no evidence of a difference in overall survival between early and delayed treatment (HR 0·98, 95% CI 0·80-1·20, p=0·85). Median survival from randomisation was 25·7 months (95% CI 23·0-27·9) for patients on early treatment and 27·1 months (22·8-30·9) for those on delayed treatment. INTERPRETATION Our findings showed no evidence of a survival benefit with early treatment of relapse on the basis of a raised CA125 concentration alone, and therefore the value of routine measurement of CA125 in the follow-up of patients with ovarian cancer who attain a complete response after first-line treatment is not proven. FUNDING UK Medical Research Council and the European Organisation for Research and Treatment of Cancer.

Primary chemotherapy versus primary surgery for newly diagnosed advanced ovarian cancer (CHORUS): an open-label, randomised, controlled, non-inferiority trial.

BACKGROUND The international standard of care for women with suspected advanced ovarian cancer is surgical debulking followed by platinum-based chemotherapy. We aimed to establish whether use of platinum-based primary chemotherapy followed by delayed surgery was an effective and safe alternative treatment regimen. METHODS In this phase 3, non-inferiority, randomised, controlled trial (CHORUS) undertaken in 87 hospitals in the UK and New Zealand, we enrolled women with suspected stage III or IV ovarian cancer. We randomly assigned women (1:1) either to undergo primary surgery followed by six cycles of chemotherapy, or to three cycles of primary chemotherapy, then surgery, followed by three more cycles of completion chemotherapy. Each 3-week cycle consisted of carboplatin AUC5 or AUC6 plus paclitaxel 175 mg/m(2), or an alternative carboplatin combination regimen, or carboplatin monotherapy. We did the random assignment by use of a minimisation method with a random element, and stratified participants according to the randomising centre, largest radiological tumour size, clinical stage, and prespecified chemotherapy regimen. Patients and investigators were not masked to group assignment. The primary outcome measure was overall survival. Primary analyses were done in the intention-to-treat population. To establish non-inferiority, the upper bound of a one-sided 90% CI for the hazard ratio (HR) had to be less than 1.18. This trial is registered, number ISRCTN74802813, and is closed to new participants. FINDINGS Between March 1, 2004, and Aug 30, 2010, we randomly assigned 552 women to treatment. Of the 550 women who were eligible, 276 were assigned to primary surgery and 274 to primary chemotherapy. All were included in the intention-to-treat analysis; 251 assigned to primary surgery and 253 to primary chemotherapy were included in the per-protocol analysis. As of May 31, 2014, 451 deaths had occurred: 231 in the primary-surgery group versus 220 in the primary-chemotherapy group. Median overall survival was 22.6 months in the primary-surgery group versus 24.1 months in primary chemotherapy. The HR for death was 0.87 in favour of primary chemotherapy, with the upper bound of the one-sided 90% CI 0.98 (95% CI 0.72-1.05). Grade 3 or 4 postoperative adverse events and deaths within 28 days after surgery were more common in the primary-surgery group than in the primary-chemotherapy group (60 [24%] of 252 women vs 30 [14%] of 209, p=0.0007, and 14 women [6%] vs 1 woman [<1%], p=0.001). The most common grade 3 or 4 postoperative adverse event was haemorrhage in both groups (8 women [3%] in the primary-surgery group vs 14 [6%] in the primary-chemotherapy group). 110 (49%) of 225 women receiving primary surgery and 102 (40%) of 253 receiving primary chemotherapy had a grade 3 or 4 chemotherapy related toxic effect (p=0.0654), mostly uncomplicated neutropenia (20% and 16%, respectively). One fatal toxic effect, neutropenic sepsis, occurred in the primary-chemotherapy group. INTERPRETATION In women with stage III or IV ovarian cancer, survival with primary chemotherapy is non-inferior to primary surgery. In this study population, giving primary chemotherapy before surgery is an acceptable standard of care for women with advanced ovarian cancer. FUNDING Cancer Research UK and the Royal College of Obstetricians and Gynaecologists.

Intra-tumoural microvessel density in human solid tumours

Over the last decade assessment of angiogenesis has emerged as a potentially useful biological prognostic and predictive factor in human solid tumours. With the development of highly specific endothelial markers that can be assessed in histological archival specimens, several quantitative studies have been performed in various solid tumours. The majority of published studies have shown a positive correlation between intra-tumoural microvessel density, a measure of tumour angiogenesis, and prognosis in solid tumours. A minority of studies have not demonstrated an association and this may be attributed to significant differences in the methodologies employed for sample selection, immunostaining techniques, vessel counting and statistical analysis, although a number of biological differences may account for the discrepancy. In this review we evaluate the quantification of angiogenesis by immunohistochemistry, the relationship between tumour vascularity and metastasis, and the clinicopathological studies correlating intra-tumoral microvessel density with prognosis and response to anti-cancer therapy. In view of the extensive nature of this retrospective body of data, comparative studies are needed to identify the optimum technique and endothelial antigens (activated or pan-endothelial antigens) but subsequently prospective studies that allocate treatment on the basis of microvessel density are required.

Imaging tumor vascular heterogeneity and angiogenesis using dynamic contrast-enhanced magnetic resonance imaging.

This article reviews the application of dynamic contrast-enhanced magnetic resonance imaging in both clinical studies and early-phase trials of angiogenesis inhibitors. Emphasis is placed on how variation in image acquisition and analysis affects the meaning and use of derived variables. We then review the potential for future developments, with particular reference to the application of dynamic contrast-enhanced magnetic resonance imaging to evaluate the heterogeneity of tumor tissues.

Dynamic contrast-enhanced MRI in clinical trials of antivascular therapies

About 100 early-phase clinical trials and investigator-led studies of targeted antivascular therapies—both anti-angiogenic and vascular-targeting agents—have reported data derived from T1-weighted dynamic contrast-enhanced (DCE)-MRI. However, the role of DCE-MRI for decision making during the drug-development process remains controversial. Despite well-documented guidelines on image acquisition and analysis, several key questions concerning the role of this technique in early-phase trial design remain unanswered. This Review describes studies of single-agent antivascular therapies, in which DCE-MRI parameters are incorporated as pharmacodynamic biomarkers. We discuss whether these parameters, such as volume transfer constant (Ktrans), are reproducible and reliable biomarkers of both drug efficacy and proof of concept, and whether they assist in dose selection and drug scheduling for subsequent phase II trials. Emerging evidence indicates that multiparametric analysis of DCE-MRI data offers greater insight into the mechanism of drug action than studies measuring a single parameter, such as Ktrans. We also provide an overview of current data and appraise the future directions of this technique in oncology trials. Finally, major hurdles in imaging biomarker development, validation and qualification that hinder a wide application of DCE-MRI techniques in clinical trials are addressed.

Antiangiogenic therapy in oncology: current status and future directions.

Angiogenesis, the formation of new blood vessels from pre-existing vessels, has been validated as a target in several tumour types through randomised trials, incorporating vascular endothelial growth factor (VEGF) pathway inhibitors into the therapeutic armoury. Although some tumours such as renal cell carcinoma, ovarian and cervical cancers, and pancreatic neuroendocrine tumours are sensitive to these drugs, others such as prostate cancer, pancreatic adenocarcinoma, and melanoma are resistant. Even when drugs have yielded significant results, improvements in progression-free survival, and, in some cases, overall survival, are modest. Thus, a crucial issue in development of these drugs is the search for predictive biomarkers-tests that predict which patients will, and will not, benefit before initiation of therapy. Development of biomarkers is important because of the need to balance efficacy, toxicity, and cost. Novel combinations of these drugs with other antiangiogenics or other classes of drugs are being developed, and the appreciation that these drugs have immunomodulatory and other modes of action will lead to combination regimens that capitalise on these newly understood mechanisms.

Biomarkers of angiogenesis and their role in the development of VEGF inhibitors

Vascular endothelial growth factor (VEGF) has been confirmed as an important therapeutic target in randomised clinical trials in multiple disease settings. However, the extent to which individual patients benefit from VEGF inhibitors is unclear. If we are to optimise the use of these drugs or develop combination regimens that build on this efficacy, it is critical to identify those patients who are likely to benefit, particularly as these agents can be toxic and are expensive. To this end, biomarkers have been evaluated in tissue, in circulation and by imaging. Consistent drug-induced increases in plasma VEGF-A and blood pressure, as well as reductions in soluble VEGF-R2 and dynamic contrast-enhanced MRI parameters have been reported. In some clinical trials, biomarker changes were statistically significant and associated with clinical end points, but there is considerable heterogeneity between studies that are to some extent attributable to methodological issues. On the basis of observations with these biomarkers, it is now appropriate to conduct detailed prospective studies to define a suite of predictive, pharmacodynamic and surrogate response biomarkers that identify those patients most likely to benefit from and monitor their response to this novel class of drugs.

Randomized Phase II Placebo-Controlled Trial of Maintenance Therapy Using the Oral Triple Angiokinase Inhibitor BIBF 1120 After Chemotherapy for Relapsed Ovarian Cancer

PURPOSE Inhibiting angiogenesis is one of the most promising avenues for new therapies for ovarian cancer. We investigated the efficacy and safety of a novel agent, BIBF 1120, a triple angiokinase inhibitor, after chemotherapy for relapsed disease. PATIENTS AND METHODS We conducted a randomized, double-blind, controlled phase II trial in 83 patients who had just completed chemotherapy for relapsed ovarian cancer, with evidence of response, but at high risk of further early recurrence. The patients were randomly assigned to receive maintenance therapy using BIBF 1120 250 mg or placebo, twice per day, continuously for 36 weeks. End points were progression-free survival (PFS), toxicity, and overall survival. RESULTS Thirty-six-week PFS rates were 16.3% and 5.0% in the BIBF 1120 and placebo groups, respectively (hazard ratio, 0.65; 95% CI, 0.42 to 1.02; P = .06). Four patients continued on BIBF 1120, including two patients for another year or more. The proportion of patients with any grade 3 or 4 adverse events was similar between the groups (34.9% for BIBF 1120 v 27.5% for placebo; P = .49; mostly grade 3). However, more patients on BIBF 1120 experienced diarrhea, nausea, or vomiting (mainly grade 1 or 2 and no grade 4). There was a higher rate of grade 3 or 4 hepatotoxicity in patients on BIBF 1120 (51.2%) compared with patients on placebo (7.5%; P < .001), but this was rarely of clinical significance, and patients continued with the trial treatment. A single-level dose reduction to 150 mg was made in 15 patients, all on active drug. CONCLUSION BIBF 1120 is well tolerated and associated with a potential improvement in PFS. The observed treatment effect is sufficient to justify further study within a large phase III trial.