Background: For > 20 years, pharmaceutical companies and academic centers have been developing bradykinin antagonists. The patent literature on these molecules (up to and including 2004) has been analyzed previously in this journal in two review articles.
Objective: The aim of this review is to provide an update (from 2005 to early 2009) on the patenting activity in the field of bradykinin antagonists (including patents on their formulation). Where possible, the information from the patents has been supplemented with that from the primary literature, clinical trial databases and company websites in an attempt to give a more complete picture.
Conclusions: In the past 4 years, nearly 50 new patents have been filed on bradykinin antagonists--in the case of several filings, only the original source has been considered in this analysis--the vast majority of these (> 93%) on B1 antagonists. However, despite this large amount of work, only one compound, icatibant--a hydrophilic decapeptide selective for the B2 receptor--has reached the market, although it needs to be administered parenterally.