4th Global CRO Council for Bioanalysis: coadministered drugs stability, EMA/US FDA guidelines, 483s and carryover

The Global CRO Council for Bioanalysis (GCC) was formed in September 2010. Since then, the representatives of the member companies come together periodically to openly discuss bioanalysis and the regulatory challenges unique to the outsourcing industry. The 4th GCC Closed Forum brought together experts from bioanalytical CROs to share and discuss recent issues in regulated bioanalysis, such as the impact of coadministered drugs on stability, some differences between European Medicines Agency and US FDA bioanalytical guidance documents and lessons learned following recent Untitled Letters. Recent 483s and agency findings, as well as issues on method carryover, were also part of the topics discussed.     

An alternative solution to overcome carryover issues in bioanalysis

LC-MS/MS instruments are considered as the analytical technique of choice for bioanalytical assays. The LC-MS/MS technique acquired this status due to its robustness, specificity, sensitivity and good precision and accuracy. Nonetheless, with the use of these instruments, users also have to deal with some complex analytical problems such as carryover. Even if carryover is well known and widely discussed, it still remains a common issue in bioanalytical work. Although new autosampler instruments manufactured are specifically designed to fix the problem, the issue is still present because methods developed by the industry also change and evolve with the instrument. Requests for wider dynamic ranges and the use of a very sensitive detector that can reach very low LOQ are among the reasons. This article reviews the causes of carryover and proposes an autosampler needle seat backflush as a novel solution to address the issue.     

Off-label use of sunitinib in patients with advanced, epithelial thyroid cancer: a retrospective analysis

Tyrosine kinase receptors play an important role in tumor angiogenesis and, their implication in epithelial thyroid tumor growth has been highlighted. Sunitinib is a novel tyrosine kinase inhibitor, approved in 2006 by Food and Drug Administration for the treatment of advanced renal cell and gastrointestinal stromal tumors. Preliminary promising results have been also obtained in patients with RAI-resistant thyroid neoplasia. In the current study, our experience on 9 patients with advanced thyroid epithelial cancer is analyzed and discussed in relation to the new patents in this field. According to RECIST criteria, partial response was obtained in 5/9 (55.5%) patients at 3 months and in 6/9 (66.6%) at 6 months. Median treatment follow-up was 13.0 months and median overall survival and progression-free survival were 20 [95% confidence interval (CI) 9.3 - 30.6] and 21 months (95% CI 6.9 - 35.1), respectively. One case of severe thoracic hemorrhage was observed, the most common adverse events being represented by fatigue, (44.4% ), skin rash (33.3% ), headache (33.3% ), and one case each of hypertension, macrocytosis and acute pneumonia. These results confirm sunitinib as a potential useful tool for the treatment of advanced thyroid cancers and may open the way for new patents of molecules with more specific target selectivity.     

Multiple Pathways Analysis of Brain Functional Networks from EEG Signals: An Application to Real Data

In the present study, we propose a theoretical graph procedure to investigate multiple pathways in brain functional networks. By taking into account all the possible paths consisting of h links between the nodes pairs of the network, we measured the global network redundancy R _h as the number of parallel paths and the global network permeability P _h as the probability to get connected. We used this procedure to investigate the structural and dynamical changes in the cortical networks estimated from a dataset of high-resolution EEG signals in a group of spinal cord injured (SCI) patients during the attempt of foot movement. In the light of a statistical contrast with a healthy population, the permeability index P _h of the SCI networks increased significantly (P < 0.01) in the Theta frequency band (3–6 Hz) for distances h ranging from 2 to 4. On the contrary, no significant differences were found between the two populations for the redundancy index R _h . The most significant changes in the brain functional network of SCI patients occurred mainly in the lower spectral contents. These changes were related to an improved propagation of communication between the closest cortical areas rather than to a different level of redundancy. This evidence strengthens the hypothesis of the need for a higher functional interaction among the closest ROIs as a mechanism to compensate the lack of feedback from the peripheral nerves to the sensomotor areas.     

Evidence of Renal Infection in Fatal Cases of 2009 Pandemic Influenza A (H1N1)

The 2009 pandemic influenza A (H1N1) caused significant morbidity and mortality. Acute lung injury is the hallmark of the disease, but multiple organ system dysfunction can develop and lead to death. Therefore, we sought to investigate whether there was postmortem evidence of H1N1 presence and virus-induced organ injury in autopsy specimens. Five cases in which patients died of influenza A (H1N1) virus infection were studied. The lungs of all patients showed macroscopic and microscopic findings already described for H1N1 (consolidation, edema, hemorrhage, alveolar damage, hyaline membrane, and inflammation), and H1N1 viruses were present in alveolar cells in immunochemical studies. Acute tubular necrosis was present in all cases, but there was no evidence of direct virus-induced kidney injury. Nevertheless, H1N1 viruses were found in the cytoplasm of glomerular macrophages in the kidneys of 4 patients. Therefore, our data provide strong evidence that H1N1 presence is not restricted to the lungs.     

Vibratory noise to the fingertip enhances balance improvement associated with light touch

Light touch of a fingertip on an external stable surface greatly improves the postural stability of standing subjects. The hypothesis of the present work was that a vibrating surface could increase the effectiveness of fingertip signaling to the central nervous system (e.g., by a stochastic resonance mechanism) and hence improve postural stability beyond that achieved by light touch. Subjects stood quietly over a force plate while touching with their right index fingertip a surface that could be either quiescent or randomly vibrated at two low-level noise intensities. The vibratory noise of the contact surface caused a significant decrease in postural sway, as assessed by center of pressure measures in both time and frequency domains. Complementary experiments were designed to test whether postural control improvements were associated with a stochastic resonance mechanism or whether attentional mechanisms could be contributing. A full curve relating body sway parameters and different levels of vibratory noise resulted in a U-like function, suggesting that the improvement in sway relied on a stochastic resonance mechanism. Additionally, no decrease in postural sway was observed when the vibrating contact surface was attached to the subject’s body, suggesting that no attentional mechanisms were involved. These results indicate that sensory cues obtained from the fingertip need not necessarily be associated with static contact surfaces to cause improvement in postural stability. A low-level noisy vibration applied to the contact surface could lead to a better performance of the postural control system.