The use of alternative methods in the search for new analgesics

Therapeutic needs ill the field of analgesia are mainly focused on the reli ef of chronic pain sustained by either inflammatory or neuropathic mechanis ms. The high diversity of physiopathological mechanisms supporting chronic pains make necessary to use many different animal models, a point that is e thically disputable. In such a way, it may he valuable to characterize the pharmacology of compounds using irt vitro assays before testing ill vivo th ose having been selected, In parallel to pharmacological evaluation, it is proposed to add physicochemical, pharmacokinetic and metabolic ir, vitro as says in the purpose to predict the availability of new chemical entities in the body. Furthermore, recombinant methodologies are now allowing to work with human targets previously introduced into competent cell lines. The ult imate goal consists to get the highest confidence in predicting in vivo act ivity and thus, limit the number of molecules to he tested in animals.