The discovery and development of Viagra® (sildenafil citrate)

Part of the Milestones in Drug Therapy MDT book series (MDT)


Sildenafil citrate (UK-92,480, Viagra®) is a selective inhibitor of phosphodiesterase type 5 (PDE5) and acts on the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) pathway [1, 2]. UK-92,480 was first synthesised in the Sandwich laboratories of Pfizer Ltd, UK in 1989, and resulted from a discovery programme aimed at developing a selective inhibitor of PDE5. The origins of the project that eventually led to the discovery and development of Viagra date from around the mid 1980s. At this time, scientists working at the Pfizer European Research Centre were interested in potential new approaches to the treatment of several cardiovascular diseases.


Nitric Oxide Erectile Dysfunction Multiple System Atrophy Erectile Function Corpus Cavernosum 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Basel AG 2004

Authors and Affiliations

  1. 1.Viagra Medical StrategiesPfizer LtdSandwich, KentUK

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