Understanding complex magnetic order in disordered cobalt hydroxides through analysis of the local structure

In many ostensibly crystalline materials, unit-cell-based descriptions do not always capture the complete physics of the system due to disruption in long-range order. In the series of cobalt hydroxides studied here, Co(OH)$_{2-x}$(Cl)$_x$(H$_2$O)$_{n}$, magnetic Bragg diffraction reveals a fully compensated N\'eel state, yet the materials show significant and open magnetization loops. A detailed analysis of the local structure defines the aperiodic arrangement of cobalt coordination polyhedra. Representation of the structure as a combination of distinct polyhedral motifs explains the existence of locally uncompensated moments and provides a quantitative agreement with bulk magnetic measurements and magnetic Bragg diffraction

Drugs in early clinical development for the treatment of osteosarcoma

Introduction: Osteosarcomas are the main malignant primary bone tumours found in children and young adults. Conventional treatment is based on diagnosis and resection surgery, combined with polychemotherapy. This is a protocol that was established in the 1970s. Unfortunately, this therapeutic approach has reached a plateau of efficacy and the patient survival rate has not improved in the last four decades. New therapeutic approaches are thus required to improve the prognosis for osteosarcoma patients. Areas covered: From the databases available and published scientific literature, the present review gives an overview of the drugs currently in early clinical development for the treatment of osteosarcoma. For each drug, a short description is given of the relevant scientific data supporting its development. Expert opinion: Multidrug targeted approaches are set to emerge, given the heterogeneity of osteosarcoma subtypes and the multitude of therapeutic responses. The key role played by the microenvironment in the disease increases the number of therapeutic targets (such as macrophages or osteoclasts), as well as the master proteins that control cell proliferation or cell death. Ongoing phase I/II trials are important steps, not only for identifying new therapies with greater safety and efficacy, but also for better defining the role played by the microenvironment in the pathogenesis of osteosarcoma

Mifamurtide for the treatment of nonmetastatic osteosarcoma

International audienceINTRODUCTION: The standard treatment for osteosarcoma requires both macroscopic surgical wide resection and postoperative multi-drug chemotherapy in neoadjuvant and adjuvant settings. However, the 5-year event-free survival has remained at a plateau of 60-70% of patients with nonmetastatic osteosarcoma for more than 30 years. AREAS COVERED: Mifamurtide (liposomal muramyl tripeptide phosphatidylethanolamine; L-MTP-PE) is a new agent. L-MTP-PE is a nonspecific immunomodulator, which is a synthetic analog of a component of bacterial cell walls. L-MTP-PE activates macrophages and monocytes as a potent activator of immune response in addition to standard chemotherapy. It also improves the overall survival from 70 to 78% and results in a one-third reduction in the risk of death from osteosarcoma. This review summarizes the most recent findings about L-MTP-PE and its therapeutic application for nonmetastatic osteosarcoma. EXPERT OPINION: Recently, L-MTP-PE has been approved in Europe for the treatment of nonmetastatic osteosarcoma with chemotherapy. L-MTP-PE in combination with traditional treatment is expected to go mainstream and to be beneficial for patients with osteosarcoma. Information about potential benefit regarding mifamurtide use in the neoadjuvant setting (i.e., before surgery) and/or usefulness of L-MTP-PE in metastatic in relapsed and metastatic osteosarcoma requires analysis of expanded access and/or future clinical trials of L-MTP-PE in high-burden and low-burden situations