PROBLEM TO BE SOLVED: To provide a treatment means and a pharmaceutical formulation of an L-enantiomer of cis-1-[2-(hydroxymethyl)-1,3-oxathiolane-5-yl]-5-fluorocytosine and its pharmaceutically acceptable derivatives for treatment of hepatitis B.SOLUTION: The use of 1-[2-(hydroxymethyl)-1,3-oxathiolane-5-yl]-5-fluorocytosine represented by formula (I), or its physiologically functional derivatives is disclosed.COPYRIGHT: (C)2011,JPO&INPIT【課題】シス-1-(2-(ヒドロキシメチル)-1,3-オキサチオラン-5-イル)-5-フルオロシトシンのL-鏡像体およびそれらの医薬上許容し得る誘導体のB型肝炎感染の治療手段及び、医薬品製剤の提供。【解決手段】下式(I)で示される1-(2-(ヒドロキシメチル)-1,3-オキサチオラン-5-イル)-5-フルオロシトシンもしくはそれらの生理学的機能性誘導体の使用。【選択図】なし
