Ketotifen  (Synonyms: 酮替芬; HC 20-511)

Ketotifen (HC 20-511) is an orally active second-generation noncompetitive histamine 1 (H1) receptor blocker and mast cell stabilizer. Ketotifen can block 6-phosphogluconate dehydrogenase (PGD) in vitro. Ketotifen also has antiviral activity against SARS-CoV-2 and Influenza virus. Ketotifen can be used to the research of autoimmune encephalomyelitis (EAE) and asthma attack prevention^[1][2][3][4].

Ketotifen (0-100 μM; 2 or 4 days) inhibits SARS-CoV-2 with an EC₅₀ of 48.9 μM; and increases the percentage inhibition of SARS-CoV-2 to 79%, 83% and 93% when co-administers with 25, 50 and 100 μM Indomethacin, respectively^[3].
Ketotifen (0-50 μM; 24 h) has inhibitory activity against PR8, pH1N1 and H3N2 with EC₅₀s of 5.9 μM, 33.7 μM and 48.5 μM, respectively; and exhibits relatively low cytotoxicity in MDCK cells (EC₅₀=291 μM)^[4].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

Ketotifen (80 mg/kg; i.g.; daily for 3 days) reduces end organ damage and mortality in mice infected with influenza virus^[4].
Ketotifen (0.4 mg/kg; i.p.; daily for 10 days) reduces encephalomyelitis (EAE) prevalence and severity^[5].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

309.43

C₁₉H₁₉NOS

34580-13-7

酮替芬

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Klooker TK, et al. The mast cell stabiliser ketotifen decreases visceral hypersensitivity and improves intestinal symptoms in patients with irritable bowel syndrome. Gut. 2010 Sep;59(9):1213-21.  [Content Brief]

  [2]. Zhang H, et al. Advances in the discovery of exosome inhibitors in cancer. J Enzyme Inhib Med Chem. 2020;35(1):1322-1330.  [Content Brief]

  [3]. Kiani P, et al. In Vitro Assessment of the Antiviral Activity of Ketotifen, Indomethacin and Naproxen, Alone and in Combination, against SARS-CoV-2. Viruses. 2021 Mar 26;13(4):558.  [Content Brief]

  [4]. Enkirch T, et al. Identification and in vivo Efficacy Assessment of Approved Orally Bioavailable Human Host Protein-Targeting Drugs With Broad Anti-influenza A Activity. Front Immunol. 2019 Jun 5;10:1097.  [Content Brief]

  [5]. Pinke KH, et al. Calming Down Mast Cells with Ketotifen: A Potential Strategy for Multiple Sclerosis Therapy? Neurotherapeutics. 2020 Jan;17(1):218-234.  [Content Brief]