Channels and transporters. Mini-symposium of the Division of Medicinal Chemistry (DMC) of the Swiss Chemical Society (SCS) at the Department of Chemistry, University of Basel, May 27, 2010

During a half-day symposium, the topic 'Channels and Transporters' was covered with five lectures, including a presentation on 'Introduction and Basics of Channels and Transporters' by Beat Ernst, lectures on structure, function and physiology of channels and transporters ('The Structural Basis for Ion Conduction and Gating in Pentameric Ligand-Gated Ion Channels' by Raimund Dutzler and 'Uptake and Efflux Transporters for Endogenous Substances and for Drugs' by Dietrich Keppler), and a case study lecture on 'Avosentan' by Werner Neidhart. The program was completed by Matthias Hediger who introduced to the audience the National Center of Competence in Research (NCCR)-TransCure in his lecture entitled 'From Transport Physiology to Identification of Therapeutic Targets'.

Lead discovery, chemistry optimization, and biological evaluation studies of novel biamide derivatives as CB2 receptor inverse agonists and osteoclast inhibitors

N,N'-((4-(Dimethylamino)phenyl)methylene)bis(2-phenylacetamide) was discovered by using 3D pharmacophore database searches and was biologically confirmed as a new class of CB(2) inverse agonists. Subsequently, 52 derivatives were designed and synthesized through lead chemistry optimization by modifying the rings A-C and the core structure in further SAR studies. Five compounds were developed and also confirmed as CB(2) inverse agonists with the highest CB(2) binding affinity (CB(2)K(i) of 22-85 nM, EC(50) of 4-28 nM) and best selectivity (CB(1)/CB(2) of 235- to 909-fold). Furthermore, osteoclastogenesis bioassay indicated that PAM compounds showed great inhibition of osteoclast formation. Especially, compound 26 showed 72% inhibition activity even at the low concentration of 0.1 μM. The cytotoxicity assay suggested that the inhibition of PAM compounds on osteoclastogenesis did not result from its cytotoxicity. Therefore, these PAM derivatives could be used as potential leads for the development of a new type of antiosteoporosis agent.

Orphan drugs and paediatric medicinal products

While the safety and availability of medicinal products for the majority of adult patients has steadily improved in recent decades, for children and people suffering from rare diseases (orphan diseases) there is a lack of approved medicinal products for these patient populations. Since the research and development of medicinal products is associated with high costs, the costs for paediatric medicinal products and medicines for rare diseases (orphan drugs) may barely be covered under normal market conditions due to the small patient populations. In order to prevent the continued exclusion of children and persons suffering from rare diseases from medical progress and to eliminate the deficits in the research and development of medicinal products for these patient groups, the European Union created, along the lines of the U.S. model, a system of incentives and constraints. Since 2000, under Regulation (EC) No. 141/2000 (Orphan Drug Regulation) there has been an incentive system to encourage the research and development of orphan drugs. With the goal of improving the health of children in Europe, Regulation (EC) No. 1901/2006 (Paediatric Regulation) combines economic incentives with the requirement to conduct paediatric studies. This article explains and comments on the specific regulatory framework for orphan drugs and paediatric medicinal products in the European Union.