Table 1.

Potential candidates drugs for the treatment of COVID‐19

S/N	Class of therapy	Example(s)	Mechanism of action	Reference(s)
1	Broad‐spectrum antivirals	β‐D‐N4‐hydroxycytidine (NHC), Dihydroorotate dehydrogenase (DHODH) Merimepodib N‐(2‐hydroxypropyl)‐3‐trimethylammonium chitosan chloride (HTCC)	Known activity against a number of human RNA viruses; reduces viral titre by introducing mutations in the viral RNA genome; Non‐competitive inhibitor of the enzyme‐ Inosine‐5´‐monophosphate dehydrogenase (IMPDH), which is involved in the biosynthesis of host guanosine and is capable of reducing the replication of SARS‐CoV‐2 in vitro; Show efficacy on less pathogenic human coronavirus HCoV‐NL63, pseudotyped SARS‐CoV‐2 and MERS‐CoV, in the airway of human epithelial cells	88 89, 90 91 92
2	Protease inhibitors	Peptidomimetic inhibitors (11a and 11b); Nelfinavir	Target the SARS‐CoV‐2 main protease (Mpro)	93, 94
3	RNA‐dependent RNA polymerase (RdRp) inhibitors	Remdesivir	Adenosine triphosphate analog that prevents RdRp as a result of binding to RNA strands and inhibiting nucleotides addition, bringing about the termination of viral RNA transcription	95
4	Glucocorticoids	Ciclesonide, mometasone and lopinavir	Reducing the function of certain aspects of the immune system such as inflammation and therefore, used in the treatment of diseases caused by an overactive immune system	96
5	JAK inhibitors (JAKinibs)	Baricitinib Ruxolitinib, memolitinib and oclacitinib	Interrupts the passage as well as the intracellular assembly of SARS‐CoV‐2 into target cells through disruption of AAK1 signalling and also reduces inflammation in patients with ARDS; target both JAK1 and JAK2 which further affects signalling pathways downstream of the receptors, involved in the development of COVID‐19; its possibility of hindering a range of inflammatory cytokines including IFN‐α, which plays a key role in reducing virus activity	97 98
6	Recombinant monoclonal antibody	Tocilizumab (TCZ)	Binds both soluble and membrane‐bound IL‐6 receptors (IL‐6R) of immunoglobulin IgG1 subtype where such binding inhibits sIL‐6R and mIL‐6R‐mediated signal transduction	99, 100
7	Chimeric monoclonal antibody	Siltuximab	Binding to IL‐6 and blocking its effect	101