THERAVANCE, INC. C H EMISTRY MULTIVALENT DRUGS:  BUILDING DRUGS FOR IMPORTANT  BIOLOGICAL TARGETS y utilizing cutting-edge medicinal chemistry technology, Alexandria client tenant Theravance, Inc., has form- ulated a new approach to the creation of innovative  multivalent drugs. Multivalency allows for the simul- taneous binding of multiple linked drug components with multiple binding sites on a biological target. These drugs have the capability to multiply a molecule’s affinity (strength of binding) and selectivity, thereby enhancing effi- cacy while minimizing negative side effects. Theravance starts  with an existing drug, then applies proprietary multivalent  technology in selecting, linking, attaching and controlling build- ing blocks of chemical compounds. As a result of this approach, Theravance has the ability to create best-in-class medicines  able to meet medical needs not addressed by currently available treatments. Theravance, in collaboration with GlaxoSmithKline, is in the process of developing new medicines with the poten- tial to transform the treatment of asthma and other debilitating respiratory diseases. B