title: Cathepsin S inhibitors: 2004-2010.
abstract: BACKGROUND
  Cathepsin S, a lysosomal cysteine protease, plays an important role in antigen presentation. Its inhibition is expected to result in immunosuppression, making this enzyme an attractive target to potentially treat autoimmune and inflammatory diseases.
  
  
  METHODS
  The focus of this review is on patent literature regarding small molecule inhibitors of cathepsin S published from 2004 to April 2010. Different structure classes based on binding strategies (covalent vs non-covalent) are surveyed and listed according to warhead type and research organization.
  
  
  CONCLUSIONS
  Although > 40 patent applications have appeared between 2004 and 2010, the decrease in applications focusing on cathepsin S over the past 2 - 3 years may reflect a renewed interest in other cathepsins, especially cathepsin K, for which a small molecule inhibitor is currently in Phase III clinical trials.
authors.affiliation: Johnson & Johnson Pharmaceutical Research & Development, L.L.C., 3210 Merryfield Row, San Diego, CA 92121, USA. alee7@its.jnj.com
authors.forename: Alice
authors.initials: A
authors.lastname: Lee-Dutra
authors.forename: Danielle K
authors.initials: DK
authors.lastname: Wiener
authors.forename: Siquan
authors.initials: S
authors.lastname: Sun
mesh_terms: D000818:Animals; D002403:Cathepsins / Q000037:antagonists & inhibitors* / Q000737:chemistry; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D006801:Humans; D010330:Patents as Topic; D013329:Structure-Activity Relationship; D013997:Time Factors
chemical_list: D004791:Enzyme Inhibitors; D002403:Cathepsins; C028217:cathepsin S