Clevudine, 克来夫定, 克拉夫定

Clevudine is a nucleoside analogue reverse transcriptase inhibitor that is used in the treatment of chronic hepatitis B. Clevudine inhibits viral replication by interfering with the synthesis of viral DNA, thereby suppressing viral replication. In vitro studies have shown that clevudine prevents the development of resistant mutants. Studies in vivo have shown that clevudine can inhibit tumor growth when administered at low doses as an anti-cancer compound. Clevudine has been shown to be effective against polymerase chain reaction (PCR)-resistant strains of HIV-1 and reduces the production of interferon alpha-2b, which may be associated with its antiviral activity. The mechanism by which clevudine exerts its antiviral activity is not yet fully understood.

Clevudine is a β-L-nucleoside analog of thymidine that has antiviral activity. It is active against hepatitis B virus (HBV) in HepG2/2.15 cells with an EC50 value of 0.1 µM. Clevudine (0.01-10 µM) reduces virion DNA in the culture supernatant of primary hepatocytes isolated from a duckling model of chronic HBV infection. Oral administration of clevudine (3 and 10 mg/kg) reduces serum viral load in a woodchuck model of chronic HBV infection.

Clevudine is a synthetic pyrimidine analogue with activity against hepatitis B virus (HBV). Intracellularly, clevudine is phosphorylated to its active metabolites, clevudine monophosphate and triphosphate. The triphosphate metabolite competes with thymidine for incorporation into viral DNA, thereby causing DNA chain termination and inhibiting the function of HBV DNA polymerase (reverse transcriptase). Clevudine has a long half-life and shows significant reduction of covalently closed circular DNA (cccDNA), therefore the patient is less likely to have a relapse after treatment is discontinued.

Clevudine is a pyrimidine 2'-deoxyribonucleoside.

Title: Clevudine

CAS Registry Number: 163252-36-6

CAS Name: 1-(2-Deoxy-2-fluoro-b-L-arabinofuranosyl)-5-methyl-2,4-(1H,3H)-pyrimidinedione

Additional Names: 1-(2-deoxy-2-fluoro-b-L-arabinofuranosyl)thymine; 2¢-fluoro-5-methyl-b-L-arabinofuranosyluridine; L-FMAU

Molecular Formula: C10H13FN2O5

Molecular Weight: 260.22

Percent Composition: C 46.16%, H 5.04%, F 7.30%, N 10.77%, O 30.74%

Literature References: Nucleoside analog; specific inhibitor of viral DNA synthesis. Prepn: C. K. Chu et al., WO 9520595; eidem, US 5587362 (1995, 1996 both to Univ. Georgia Res. Found.; Yale Univ.); T. Ma et al., J. Med. Chem. 39, 2835 (1996). Synthesis: M. L. Sznaidman et al., Nucleosides Nucleotides Nucleic Acids 21, 155 (2002). In vitro antiviral activity: C. K. Chu et al., Antimicrob. Agents Chemother. 39, 979 (1995). Pharmacokinetics: J. D. Wright et al., Pharm. Res. 12, 1350 (1995). Mechanism of action study: Y. Chong, C. K. Chu, Bioorg. Med. Chem. Lett. 12, 3459 (2002). Clinical evaluation in chronic hepatitis B: P. Marcellin et al., Hepatology 40, 140 (2004). Review of preclinical pharmacology: C. K. Chu et al. in Therapies for Viral Hepatitis, R. F. Schinazi et al., Eds. (Int. Med. Press, London, 1998) pp 303-312; of development and clinical experience: G. R. Painter et al. in Frontiers in Viral Hepatitis, R. F. Schinazi et al., Eds. (Elsevier, New York, 2003) pp 281-300.

Properties: Crystals from methanol/chloroform, mp 184-185°. [a]D25 -111.77° (c = 0.23 in methanol). uv max in water: 265.0 (pH 2), 265.5 (pH 7), 265.5 nm (pH 11) (e 9695, 9647, 7153). LD50 in mice, rats (mg/kg): >5000, >3000 orally (Painter).

Melting point: mp 184-185°

Optical Rotation: [a]D25 -111.77° (c = 0.23 in methanol)

Absorption maximum: uv max in water: 265.0 (pH 2), 265.5 (pH 7), 265.5 nm (pH 11) (e 9695, 9647, 7153)

Toxicity data: LD50 in mice, rats (mg/kg): >5000, >3000 orally (Painter)

Derivative Type: Triphosphate

CAS Registry Number: 174625-00-4

Additional Names: L-FMAU-TP

Molecular Formula: C10H16FN2O14P3

Molecular Weight: 500.16

Percent Composition: C 24.01%, H 3.22%, F 3.80%, N 5.60%, O 44.78%, P 18.58%

 Therap-Cat: Antiviral.

Keywords: Antiviral; Purines/Pyrimidinones.