Anticancer activity of the type I insulin-like growth factor receptor antagonist, ganitumab, in combination with the death receptor 5 agonist, conatumumab.

Agents targeting the insulin-like growth factor receptor type 1 (IGF1R) have shown antitumor activity. Based on the evidence for interaction between the IGF-1 and TRAIL pathways, we hypothesized that the combination of ganitumab (monoclonal antibody to IGF1R) with the pro-apoptotic death receptor 5 agonist, conatumumab, might increase antitumor response. Ganitumab and conatumumab were tested in combination in a Colo-205 xenograft model. Part 1 of the clinical study was a phase Ib program of three doses of conatumumab (1, 3, 15 mg/kg) in combination with 18 mg/kg ganitumab to determine the maximum tolerated dose (MTD) in patients with advanced solid tumors. Part 2 was conducted in six cohorts with advanced non-small cell lung cancer (squamous or non-squamous histology), colorectal cancer, sarcoma, pancreatic cancer, or ovarian cancer, treated at the recommended doses of the combination. The combination was significantly more active in the Colo-205 xenograft model than either single agent alone (p < 0.0015). In part 1 of the clinical study, no dose-limiting toxicities were observed and the MTD of conatumumab was 15 mg/kg in combination with 18 mg/kg ganitumab. In part 2, 78 patients were treated and there were no objective responses but 28 patients (36 %) had stable disease (median 46 days, range 0-261). The combination was well-tolerated with no new toxicities. In conclusion, the combination of ganitumab and conatumumab was well-tolerated but had no objective responses in the population tested. The successful future application of this combination of antitumor mechanisms may rely on the identification of predictive biomarkers.

Methodological quality of meta-analyses: matched-pairs comparison over time and between industry-sponsored and academic-sponsored reports.

CONTEXT: Meta-analyses are regularly used to inform healthcare decisions. Concerns have been expressed about the quality of meta-analyses and, in particular, about those supported by the pharmaceutical industry. OBJECTIVE: The objective of this study is to compare the quality of pharmaceutical-industry-supported meta-analyses with academic meta-analyses and of meta-analyses published before and after companies started to disclose their data. DATA SOURCES: We identified industry-supported meta-analyses by searching the Scopus bibliographic database, using author affiliations. We matched each industry-supported meta-analysis with an academic meta-analysis using high-level MeSH terms in PubMed. STUDY SELECTION: We included meta-analyses of randomized trials assessing the efficacy or safety of any pharmaceutical intervention in humans, published in 2002-2004 or 2008-2009. Cochrane reviews were excluded. Two individuals independently selected papers, with discrepancies resolved by two further individuals. ASSESSMENT: We developed and piloted a quality-assessment tool, consisting of 43 questions in four domains, with a key summary question covering each domain. Two individuals independently assessed each meta-analysis. RESULTS: We examined 126 meta-analysis publications in 63 matched pairs. The average quality was low, with fewer than 50% adequate in three of the four domains. Industry-supported meta-analyses less often demonstrated adequate methods for locating studies and assessing their quality (odds ratio 0.44, 95% confidence interval 0.21 to 0.92), for analysing the included studies (0.52, 0.25 to 1.06), for undertaking meta-analyses (0.82, 0.40 to 1.68) and in reaching sound conclusions (0.62, 0.30 to 1.28). Quality generally improved over time, particularly for some aspects of industry reports. CONCLUSIONS: Academic meta-analysis papers are generally of higher quality than industry-supported ones. This is largely due to less detailed reporting in industry-supported meta-analyses and a tendency for them to take the included studies at face value, probably arising from the implicit assumption that these studies already have high methodological standards to meet licensing requirements. The improved quality over time does not appear to be due to the use of data disclosed by industry. The main limitations of this study are the small sample of papers and the subjective nature of some of the assessment processes.

A tool to assess the quality of a meta-analysis.

BACKGROUND: Because meta-analyses are increasingly prevalent and cited in the medical literature, it is important that tools are available to assess their methodological quality. When performing an empirical study of the quality of published meta-analyses, we found that existing tools did not place a strong emphasis on statistical and interpretational issues. METHODS: We developed a quality-assessment tool using existing materials and expert judgment as a starting point, followed by multiple iterations of input from our working group, piloting, and discussion. After having used the tool for our empirical study, agreement for four key items in the tool was measured using weighted kappa coefficients. RESULTS: Our tool contained 43 items divided into four key areas (data sources, analysis of individual studies, meta-analysis methods, and interpretation), and each area ended with a summary question. We also produced guidance for completing the tool. Agreement between raters was fair to moderate. CONCLUSIONS: The tool should usefully inform subsequent initiatives to develop quality-assessment tools for meta-analysis. We advocate use of consensus between independent raters when assessing statistical appropriateness and adequacy of interpretation in meta-analyses.

Randomized trial of darbepoetin alfa for treatment of renal anemia at a reduced dose frequency compared with rHuEPO in dialysis patients.

BACKGROUND: Darbepoetin alfa is a glycoprotein with a three-fold longer terminal half-life than recombinant human erythropoietin (rHuEPO). We aimed to determine whether darbepoetin alfa is as effective and well tolerated as rHuEPO for treating renal anemia in dialysis patients when administered at a reduced dose frequency. METHODS: A total of 522 European and Australian hemodialysis and peritoneal dialysis patients receiving stable rHuEPO therapy by either the intravenous (IV) or subcutaneous (SC) route were randomized, open-label in a 1:2 ratio to continue rHuEPO or to receive an equivalent dose of darbepoetin alfa at a reduced dose frequency. Patients receiving rHuEPO once weekly changed to once every other week darbepoetin alfa, and those receiving rHuEPO two or three times weekly changed to once-weekly darbepoetin alfa. The doses of rHuEPO and darbepoetin alfa were titrated to maintain hemoglobin close to the patient's baseline level for up to 52 weeks. The primary endpoint was the change in hemoglobin between baseline and the evaluation period at weeks 25 to 32 of treatment. RESULTS: The mean change in hemoglobin from baseline to the evaluation period was similar in the darbepoetin alfa (-0.03 g/dL; SE 0.11) and rHuEPO (-0.06 g/dL; SE 0.13) groups, and the difference between the two treatments was 0.03 g/dL (95% CI -0.16, 0.21). This was not a statistically significant or clinically relevant difference, despite the reduced frequency of darbepoetin alfa administration. At the end of the evaluation period, >/=95% of patients had their hemoglobin successfully maintained on their assigned dose frequency for darbepoetin alfa (once weekly and once every other week) and rHuEPO (once, twice and three times weekly). The safety profiles of darbepoetin alfa and rHuEPO were similar, and no antibodies to either treatment were detected. CONCLUSIONS: Darbepoetin alfa maintains hemoglobin as effectively as rHuEPO, but with a reduced dose frequency.