Niclosamide

Name Niclosamide
Synonyms Bayluscid; 2′,5-Dichloro-4′-nitrosalicylanilide; 2-Hydroxy-5-chloro-N-(2-chloro-4-nitrophenyl)benzamide; 5-Chloro-2′-chloro-4′-nitrosalicylanilide; 5-Chloro-N-(2-chloro-4-nitrophenyl)salicylamide

Molecular Formula C13H8Cl2N2O4
Molecular Weight 327.12
CAS Registry Number 50-65-7
EINECS 200-056-8

Niclosamide is an antihelminthic used for the treatment of tapeworm infections. Helminths (worms) are multicellular organisms that infect very large numbers of humans and cause a broad range of diseases. Over 1 billion people are infected with intestinal nematodes, and many millions are infected with filarial nematodes, flukes, and tapeworms. They are an even greater problem in domestic animals.

Niclosamide is an orally bioavailable chlorinated salicylanilide, with anthelmintic and potential antineoplastic activity. Upon oral administration, niclosamide specifically induces degradation of the androgen receptor (AR) variant V7 (AR-V7) through the proteasome-mediated pathway. This downregulates the expression of the AR variant, inhibits AR-V7-mediated transcriptional activity, and reduces AR-V7 recruitment to the prostate-specific antigen (PSA) gene promoter. Niclosamide also prevents AR-V7-mediated STAT3 phosphorylation and activation. This inhibits AR/STAT3-mediated signaling and prevents expression of STAT3 target genes. Altogether, this may inhibit growth of AR-V7-overexpressing cancer cells. The AR-V7 variant, which is encoded by contiguous splicing of AR exons 1/2/3/CE3, is upregulated in a variety of cancer cell types, and is associated with both cancer progression and resistance to AR-targeted therapies.

Niclosamide is used for the treatment of most tapeworm infections. Helminths (worms) are multicellular organisms that infect very large numbers of humans and cause a broad range of diseases. Over 1 billion people are infected with intestinal nematodes, and many millions are infected with filarial nematodes, flukes, and tapeworms. They are an even greater problem in domestic animals.

Niclosamide is a member of benzamides.