||Special Feature Article
Research and Development of Quinolones in Daiichi Sankyo Co., Ltd.
Shogo Atarashi, PhD
Senior Advisor, Marketing Department, ASCA Company, Daiichi Sankyo Co., Ltd., Tokyo, Japan
Quinolones, which are antimicrobials first launched in the 1960s, have exhibited expanded significance in the clinical setting roughly every two decades. The first-generation quinolones were used for the treatment of intestinal and urinary tract infections because of their antimicrobial efficacy against Gram-negative bacteria. During the 1980s, quinolones emerged as broad-spectrum "new quinolones." During the 2000s, quinolones were used for the treatment of a wide variety of infectious diseases, mainly respiratory tract infections, as "respiratory quinolones." During these periods, innovative quinolones representative of each period were produced. Daiichi Pharmaceutical Co., Ltd. (currently Daiichi Sankyo Co., Ltd.) has continued the discovery and research and development of quinolones for more than 40 years, and has released four quinolones, including three in-house development products and one licensed-in product, that have been highly acknowledged by healthcare professionals who treat bacterial infections all over the world.
This document describes the basic concept of drug discovery research of Daiichi's three original quinolones, i.e., ofloxacin, levofloxacin, and sitafloxacin, particularly from the perspective of medicinal chemistry.