Carbohydrate prolectin-M, a galectin-3 antagonist, blocks SARS-CoV-2 activity


  • Alben Sigamani Research Consultancy, Senior Consultant, Clinical Research, Bangalore, India
  • Hana Chen-Walden Medical officer, Bioxytran
  • Jayeeta Pahan Murli Krishna Pharma Pvt. Ltd., Deputy General Manager, Ranjangaon, Maharashtra, India
  • Michelle C. Miller Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, 6-155 Jackson Hall, Minneapolis, MN 55101 USA
  • Kevin H. Mayo Department of Biochemistry, Molecular Biology & Biophysics, University of Minnesota, 6-155 Jackson Hall, Minneapolis, MN 55101 USA
  • David Platt Chief Chemist, Bioxytran,


carbohydrate prolactin, blocks SARS-CoV-2 activity, COVID-19 disease


The SARS-COV-2 (severe acute respiratory syndrome coronavirus 2) virus binds to human lectins to gain entry into cells to replicate. Blocking the virus’s entry using a complex polysaccharide component of [a (1-6)- D-mannopyranose termed “ProLectin M” has an effect on viral replication as a therapeutic tool and a safe alternative to existing antiviral therapies. Little is known about how galectin-3 inhibits viral entry into cells and its impact on the course of viral infection. Here, we investigated the effect of these non-cytotoxic polysaccharides on Vero cells infected with SARS-CoV-2 and demonstrated a dose-dependent reduction in viral load over a 48-hour viral incubation period. A pilot clinical study in five patients with laboratory-confirmed COVID-19 disease was treated with an oral formulation of ProLectin M, and all patients achieved complete disease remission with zero hospitalization or need for oxygen support. Moreover, the viral load was significantly lowered within 2 days of drug administration. On the viral envelope, glycans often play a crucial role in enabling pathogen transmission and/or entry into susceptible target cells. On the molecular level, our NMR spectroscopic studies show that ProLectin M binds relatively strongly to galectin-3, supporting the idea of an antagonist effect on the lectin. 


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How to Cite

Sigamani, A., Chen-Walden, H., Pahan, J., Miller, M. C., Mayo, K. H., & Platt, D. (2022). Carbohydrate prolectin-M, a galectin-3 antagonist, blocks SARS-CoV-2 activity. International Journal of Health Sciences, 6(S4), 6671–6683.



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