Assessment of the biological and pharmacological effects of the ανβ3 and ανβ5 integrin receptor antagonist, cilengitide (EMD 121974), in patients with advanced solid tumors

BACKGROUND

Cilengitide, an antiangiogenic agent that inhibits the binding of integrins alpha(nu)beta(3) and alpha(nu)beta(5) to the extracellular matrix, was studied at two dose levels in cancer patients to determine the optimal biological dose.

PATIENTS AND METHODS

The doses of cilengitide were 600 or 1200 mg/m(2) as a 1-h infusion twice weekly every 28 days. A novel dose escalation scheme was utilized that relied upon the biological activity rate.

RESULTS

Twenty patients received 50 courses of cilengitide with no dose-limiting toxic effects. The pharmacokinetic (PK) profile revealed a short elimination half-life of 4 h, supporting twice weekly dosing. Of the six soluble angiogenic molecules assessed, only E-selectin increased significantly from baseline. Analysis of tumor microvessel density and gene expression was not informative due to intrapatient tumor heterogeneity. Although several patients with evaluable tumor biopsy pairs did reveal posttreatment increases in tumor and endothelial cell apoptosis, these results did not reach statistical significance due to the aforementioned heterogeneity.

CONCLUSIONS

Cilengitide is a well-tolerated antiangiogenic agent. The biomarkers chosen in this study underscore the difficulty in assessing the biological activity of antiangiogenic agents in the absence of validated biological assays.

A phase I study of AEE788, a multitargeted inhibitor of ErbB and VEGF receptor family tyrosine kinases, to determine safety, PK and PD in patients (pts) with advanced colorectal cancer (CRC) and liver metastases

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Background: AEE788 (AEE) is an oral inhibitor with potent activity against EGFR, ErbB2, and KDR. This phase I study was to assess the safety, PK, PD, and MTD/DLT of AEE in pts with CRC and liver metastases. Methods: AEE was given PO at 25, 50, 100, 250, 300 or 400 mg/day daily in 28-day cycles (C) to 3–6 pt cohorts. 24-hr PK was obtained on C1, days (D)1, 15 and 28. PK parameters of AEE and active metabolite, AQM674 (AQM) were computed by non-compartmental methods. PD markers were analyzed in skin (SK), and tumor (TU) biopsies pre- and post-treatment. Samples were evaluated by both IHC and Laser Scanning Cytometry (LSC). DCE-MRI was performed at baseline (BL), and on C1D2 and 28 and C2D28. Results: 22 pts were treated at doses of 25 (n=4), 50 (n=3), 100 (n=4), 250 (n=1), 300 (n=4), and 400 mg (n=6). No DLT was reported. The most common AE (> 15%): fatigue (55%), vomiting (46%), diarrhea (41%), nausea (36%), dyspnoea (23%), constipation (18%) pyrexia (18%) and rash (18%). 2 pts had reversible gr 3/4 LFTs. Serum concentration of AEE and AQM increases with dose and dose duration. 7 pts had stable disease at the end of C2. Median time on treatment was 56 days (range 7–168). In SK, at doses =100 mg, pEGFR, pMAPK and Ki67 were inhibited by an average of 51, 54 and 41%, respectively by IHC. In endothelial cell (EC) pKDR/KDR was significantly inhibited (4-fold) in the wound-induced SK in a dose-dependent manner by LSC. In TU, inhibition of pEGFR, pMAPK and Ki67 at 400 mg was 100%, 90% and 39%, respectively by IHC. EC pKDR decreased with dose, however, trend was not significant. 1 out 15 pts who had BL and end of C1 DCE-MRI had > 40% Ktrans reduction. Conclusions: A dose dependent inhibition of pKDR, pEGFR, and pMAPK in skin and tumor was observed. However, no significant effects were observed on Ki67 and apoptosis in TU. No dose dependent reduction in Ktrans from DCE-MRI was observed. These findings were consistent with the lack of clinical activity of AEE up to 400 mg in this patient population. The study has been discontinued without reaching DLT due to safety data from other phase I studies and in favor of different dosing schedules.

No significant financial relationships to disclose.

Halophilic and halotolerant bacteria from river waters and shallow groundwater along the Rouge River of southeastern Michigan

The use of sodium chloride to melt highway and road snow is believed to have a significant effect on the groundwater ecosystem of the rivers where the salt from the roads drain. As the river composition changes, the bacterial population also changes to favour those bacteria that are more suited to the higher salt concentrations. In this experiment, we surveyed the cultivable salt-loving organisms (halophiles) on three sites that encompass the Rouge River (Lotz; site 1, Lilly, site; 8, and Ford Field, site 9). A total of 125 isolates were surveyed. Representative isolates of distinct morphologies were subjected to physiological test, using API strips and identified by 16 rDNA sequence analysis. The 16S rDNA sequences were analyzed and compared with sequences from Genbank. Results indicated that the SSU rRNA sequences of the bacterial isolates were similar to six major genera, Bacillus, Staphylococcus, Halobacillus, Paenabacillus, Halomonas, and Clostridium. Half of the isolates sequenced were similar to Bacillus spp. The API assay showed that the majority of the isolates were positive for the enzymes tryptophane deaminase, gelatinase and beta-galactosidase. Indole production, acetoin production and citrate utilization were not observed for any isolates. Fermentation of carbohydrates was observed for very few isolates. The primary enzyme found in all isolates was arginine dihydrolase, which might be an indicator of the presence of such enzyme in halophilic and halotolerant bacteria present in the Rouge River.

Non-invasive assessment of tumor proliferation using triple quantum filtered 23/Na MRI: technical challenges and solutions

We address the development of triple-quantum-filtered sodium MRI as a non-invasive surrogate measure for cell proliferation in brain tumors. We demonstrate that through careful consideration of the theoretical description of the signal, triple-quantum-filtered sodium images of adequate signal-to-noise ratio (SNR) can be acquired in clinically acceptable imaging times.

Regulatory perspective on clinical trials and end points for female sexual dysfunction, in particular, hypoactive sexual desire disorder: formulating recommendations in an environment of evolving clinical science

This article examines the history, current status, and potential future challenges in the development of drugs for female sexual dysfunction (FSD) from the perspective of the United States Food and Drug Administration. In particular, the article focuses on testosterone therapy for hypoactive sexual desire disorder (a component of FSD), and the role of the Division of Reproductive and Urologic Products in facilitating the development of safe and effective therapies for this indication.

Person-task-context: a model for designing curriculum and in-training assessment in postgraduate education

Structured curricula for senior house officers have often been lacking. The aim of this study was to trial a person-task-context model in designing a curriculum and in-training assessment (ITA) programme for SHOs in internal medicine. A working group designed the programme based on triangulation of information from interviews with trainees and programme directors, analysis of patient case mix and national quality assurance data. The interview data showed that the main difference currently between trainee levels was in expected degree of responsibility for patient management rather than in actual tasks. Key learning needs were how to take a structured approach to the tasks and get an overview of situations. SHOs expressed a need for explicit learning goals and standards of performance. SHOs requested formal teaching in non-medical aspects of competence such as communication, interpersonal skills and professionalism. This article points out how consideration of the type of trainees involved, the tasks they must do and learn, and the context in which they work are important in designing postgraduate curricula. The person-task-context model can be used to tailor curricula and ITA that support learning and may be especially beneficial in promoting learning in non-dominant areas of a specialty.

Development of an integrated-care delivery model for post-fracture care in Ontario, Canada

INTRODUCTION

The purpose of this study was to develop an integrated-care model for patients at highest risk for osteoporosis, those with a low-trauma fracture. Specific objectives were to describe the current processes and patterns of post-fracture care in hospitals in Ontario; to examine health-care professional and patient awareness of osteoporosis and the roles and responsibilities of various organizations and health care professionals; and to identify barriers and facilitators and obtain feedback on the model.

METHODS

In 2002, questionnaires were completed for 178 eligible hospitals.

RESULTS

Only 65% of hospitals inform primary-care physicians of a fracture for all patients and only 4% indicated that they provide information about osteoporosis. The main themes that emerged from the four patient focus groups (n=21) were lack of continuity of care, the absence of a link between the fracture and osteoporosis by both patients and health care providers, and need for information. Most participants agreed that something was needed to prompt their primary-care physician to investigate for osteoporosis. The four physician focus groups (n=26) identified a role for orthopaedic surgeons to flag cases.

CONCLUSIONS

From 34 key informant interviews with community-based organizations, we found a lack of integration between health care professionals who provide fracture care and those who provide osteoporosis management and fall prevention. Based on these data, we developed an integrated local-resource-based post-fracture care model, which we obtained feedback on at a stakeholder consultation workshop. The model focuses on improving emergency department/fracture clinic communication, emphasizes the need for follow-up investigation by family physicians for osteoporosis, and incorporates other health care professionals and a telemedicine multidisciplinary osteoporosis clinic. We are currently evaluating whether this model leads to an increase in appropriate investigation of and treatment for osteoporosis in patients with low-trauma fractures.

Early U.S. outcomes of laparoscopic gastric bypass versus laparoscopic adjustable silicone gastric banding for morbid obesity

Laparoscopic gastric bypass (LGBP) is the gold standard operation for long-term weight control in the United States. Laparoscopic adjustable silicone gastric banding (LASGB) is the preferred operative method for morbid obesity worldwide. Limited data are available comparing the two procedure in the United States. This study compares weight loss, complications, and early outcome of comorbidity resolution in patients who underwent LGBP versus LASGB. A review of prospectively collected data was performed on 392 patients undergoing primary LGBP (n = 232) and LASGB (n = 160) procedures between February 2001 and July 2004. Differences in percentage excess weight lost (%EWL) at 3, 6, 12, 18, and 24 months postop, improvement or resolution of comorbidities, and complications across procedure types were evaluated. Mean initial body mass index between groups was not significantly different (LGBP 47.2 vs LASGB 47.1, p < 0.53). There were significant differences in age, gender, and self-reported sweet-eating behavior between operative groups. There was a significantly greater %EWL in patients who underwent LGBP compared to patients of the LASGB groups 3, 6, 12, and 18 months after surgery. There were no significant differences in resolution or improvement of comorbidities between the groups. Although LGBP patients experienced more complications compared to LASGB patients (5.6 vs 4.3%, respectively; p < 0.56), this did not reach statistical significance. Early after surgery, LGBP patients lose more weight than LASGB patients but have similar improvements in comorbidities. Further follow-up is needed to determine the relative long-term efficacy of these procedures.