Institutionally chartered Data and Safety Monitoring Boards: structured approaches to assuring participant safety in clinical research.

Data and Safety Monitoring Boards (DSMBs) derived from the need to monitor large federally funded multi-center clinical trials and evolved to include commercial and other large and complex trials. Eventually, academic health centers also created institutionally focused trial monitoring mechanisms. The basic general principles that define traditional DSMBs extend to the institutional level. The primary responsibilities are assuring safety of the participants, preserving the integrity of the trial, and ensuring the reliability of the results. Institutionally chartered DSMBs meet these responsibilities but usually have fewer members, have a structure specific to the needs of the trial, are more focused and/or have different scope reviewing smaller, single site, higher risk, and investigator-initiated studies and are flexible to accommodate institution-specific requirements and approaches. Their purpose is to meet the responsibilities of oversight for safety and data integrity, ensure proper study design, rigor and conduct, as well as provide statistical support appropriate to the setting of the research. Academic health centers should recognize the importance and existence of institution level safety and data monitoring and provide support as much as possible. Investigators should have sufficient resources available to assemble DSMBs. The Clinical and Translational Science Awards Collaborative DSMB Workgroup provides an online manual to assist investigators.

Tumor-specific targeting by Bavituximab, a phosphatidylserine-targeting monoclonal antibody with vascular targeting and immune modulating properties, in lung cancer xenografts.

Bavituximab is a chimeric monoclonal antibody with immune modulating and tumor-associated vascular disrupting properties demonstrated in models of non-small cell lung cancer (NSCLC). The molecular target of Bavituximab, phosphatidylserine (PS), is exposed on the outer leaflet of the membrane bi-layer of malignant vascular endothelial cells and tumor cells to a greater extent than on normal tissues. We evaluated the tumor-targeting properties of Bavituximab for imaging of NSCLC xenografts when radiolabeled with (111)In through conjugation with a bifunctional chelating agent, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA). In vitro binding of (111)In-DOTA-Bavituximab to PS was determined by enzyme-linked immunosorbent assay (ELISA). Biodistribution of (111)In-DOTA-Bavituximab was conducted in normal rats, which provided data for dosimetry calculation. Single-photon emission computed tomography/computed tomography (SPECT/CT) imaging was performed in athymic nude rats bearing A549 NSCLC xenografts. At the molar conjugation ratio of 0.54 DOTA per Bavituximab, the PS binding affinity of (111)In-DOTA-Bavituximab was comparable to that of unmodified Bavituximab. Based on the quantitative SPECT/CT imaging data analysis, (111)In-DOTA-Bavituximab demonstrated tumor-specific uptake as measured by the tumor-tomuscle ratio, which peaked at 5.2 at 72 hr post-injection. In contrast, the control antibody only presented a contrast of 1.2 at the same time point.These findings may underlie the diagnostic efficacy and relative low rates of systemic vascular and immune-related toxicities of this immunoconjugate. Future applications of (111)In-DOTA-bavituximab may include prediction of efficacy, indication of tumor immunologic status, or characterization of radiographic findings.