PRE-EXISTINGÂ TREATMENTS
Chloroquine/Hydroxychloroquine
Chloroquine is used to prevent or treat malaria caused by mosquito bites. Chloroquine belongs to a class of drugs known as antimalarials.
Chloroquine
4-N-(7-chloroquinolin-4-yl)-1-N,1-N-diethylpentane-1,4- diamine
C18H26ClN3
Hydroxychloroquine
2-[4-[(7-chloroquinolin-4-yl)amino]pentyl-ethylamino]ethanol
C18H26ClN3O
CHLOROQUINE/HYDROXYCHLOROQUINE
How does it work?
1) Chloroquine is alkaline. When it is absorbed by the cell it inhibits the function of vacuoles (endosomes) carrying the virus. It does this by increasing the pH (alkalizing) of the endosomes. These endosomes are normally acidic and due to the change in their pH, they do not work properly, inhibiting the process of endocytosis by which the virus enters the cell. This effectively means the virus is unable to infect the cell and replicate and therefore will die.
2) Chloroquine is also a zinc ionophore which means it allows zinc(II) which can normally not enter cells to enter the cell by attaching to chloroquine. The increase in the concentration of zinc(II) inhibits the RNA- dependent RNA polymerase (RDRP) which is responsible for replication of viral RNA. This means that the +SSRNA from the SAR-COV-2 cannot replicate in the cell effectively stopping the production of more viruses.
3) Additionally, Chloroquine also binds to sialic acid on the cell surface membrane of the cell. This blocks the ACE-2 Receptor that the S-spike protein on the SAR-COV-2 virus needs to bind to in order to enter the cell. Therefore, chloroquine stops the virus from being able to enter the cell by blocking this receptor.
