Adenosine receptors as drug targets - what are the challenges?

Department of Neurology and Pharmacology, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
dressNature Reviews Drug Discovery (Impact Factor: 37.23). 03/2013; 12(4):265-286. DOI: 10.1038/nrd3955
Source: PubMed

ABSTRACT Adenosine signalling has long been a target for drug development, with adenosine itself or its derivatives being used clinically since the 1940s. In addition, methylxanthines such as caffeine have profound biological effects as antagonists at adenosine receptors. Moreover, drugs such as dipyridamole and methotrexate act by enhancing the activation of adenosine receptors. There is strong evidence that adenosine has a functional role in many diseases, and several pharmacological compounds specifically targeting individual adenosine receptors - either directly or indirectly - have now entered the clinic. However, only one adenosine receptor-specific agent - the adenosine A2A receptor agonist regadenoson (Lexiscan; Astellas Pharma) - has so far gained approval from the US Food and Drug Administration (FDA). Here, we focus on the biology of adenosine signalling to identify hurdles in the development of additional pharmacological compounds targeting adenosine receptors and discuss strategies to overcome these challenges.

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May 15, 2014