Biomarkers of Sarcopenia in Clinical Trials—Recommendations from the International Working Group on Sarcopenia

Sarcopenia, the age-related skeletal muscle decline, is associated with relevant clinical and socioeconomic negative outcomes in older persons. The study of this phenomenon and the development of preventive/therapeutic strategies represent public health priorities. The present document reports the results of a recent meeting of the International Working Group on Sarcopenia (a task force consisting of geriatricians and scientists from academia and industry) held on June 7–8, 2011 in Toulouse (France). The meeting was specifically focused at gaining knowledge on the currently available biomarkers (functional, biological, or imaging-related) that could be utilized in clinical trials of sarcopenia and considered the most reliable and promising to evaluate age-related modifications of skeletal muscle. Specific recommendations about the assessment of aging skeletal muscle in older people and the optimal methodological design of studies on sarcopenia were also discussed and finalized. Although the study of skeletal muscle decline is still in a very preliminary phase, the potential great benefits derived from a better understanding and treatment of this condition should encourage research on sarcopenia. However, the reasonable uncertainties (derived from exploring a novel field and the exponential acceleration of scientific progress) require the adoption of a cautious and comprehensive approach to the subject

Discovery of Highly Potent and Selective CXCR4 Inhibitors Using Protein Epitope Mimetics (PEM) Technology

Novel, highly potent CXCR4 inhibitors with good pharmacokinetic properties were obtained by applying PEM technology starting from the naturally occurring ?-hairpin peptide polyphemusin II. The design involved incorporation of key residues from polyphemusin II into a macrocyclic template-bound ?-hairpin mimetic. Using a parallel synthesis approach, the potency and ADME properties of the mimetics were optimized, resulting in CXCR4 inhibitors such as POL2438 and POL3026. Their activities were confirmed in a series of in vitro HIV-1 infection assays. Besides high selectivity for CXCR4, POL3026 had excellent plasma stability and favorable pharmacokinetic properties in dogs. In a murine model POL3026 was highly efficacious in hematopoietic stem cell mobilization. Hence, PEM-based CXCR4 inhibitors have the potential to become therapeutic agents for the treatment of HIV infections (as entry inhibitor), cancer (e.g. for inhibition of metastasis), stem cell transplant and inflammation