COVID-19 treatment: therapeutic targets and mechanisms of action

Monoclonal antibodies or recombinant decoys that specifically bind the receptor-binding domain (RBD) of the spike protein, preventing attachment to ACE2 receptors on host cells1,2.

Monoclonal antibodies binding conserved epitopes within the spike protein's S2 domain, inhibiting viral fusion and preventing the virus from entering host cells after initial ACE2 binding.

Targeting the proteolytic cleavage sites (S1/S2 and S2') of the spike protein to prevent the conformational changes required for membrane fusion2-4.

Monoclonal antibodies that bind to the N-terminal domain of the spike protein, which can disrupt viral attachment and entry5.

Compounds that lock the spike protein in its pre-fusion conformation, preventing the structural changes required for membrane fusion2,5,6.

Targeting the extensive glycan shield on the spike protein that protects key epitopes from immune recognition and may play a role in host cell binding.

Blocking the fusion process of SARS-CoV-2 with host cells by targeting HR1/HR2 domains2,5.

Small molecules that inhibit the fusion of the SARS-CoV-2 viral envelope with host cell membranes by directly targeting viral spike protein interactions or altering membrane properties critical for fusion5,7,8.

Compounds that have shown potential in inhibiting SARS-CoV-2 entry by binding to the spike protein, preventing its proteolytic cleavage necessary for viral entry3.

Stabilization of disordered states in the spike protein, particularly in the S2 subunit, preventing the conformational changes required for membrane fusion and viral entry9.

Small molecules that bind the hydrophobic cleft between RBD helices α1-α2 (site 2). Binding (Phe338/Phe342/Phe374/Trp436) can be partially occluded by the Asn343 glycan but nevertheless allosterically perturbs RBD dynamics, reduces ACE2 interaction, and disfavors the open state6.

Ligands of the linoleic-acid pocket (Tyr365/Tyr369/Phe374/Phe377/Tyr380) that stabilize the closed Spike trimer and indirectly reduce ACE2 binding; behaves as an allosteric “lock” on the RBD6.

ZDHHC5-mediated palmitoylation of the S cytosolic tail is needed for S-mediated fusion and efficient virion production; lowering palmitate supply or palmitoylation blocks infectivity10.

A strictly conserved triad of amino acids (Q134-F135-N137) in the Spike N-terminal domain (NTD) acts as a "conformational transducer." Upon binding to host gangliosides, this triad initiates an allosteric "conformational wave" that propagates through the NTD to unmask the RBD on the neighboring protomer5.

Computationally designed homotrimeric proteins (minibinders) that simultaneously engage all three receptor-binding domains (RBDs) of the SARS-CoV-2 spike trimer. This trivalent binding mode generates picomolar avidity, locking the trimer to prevent ACE2 interaction, and may confer resilience against viral escape mutations that defeat monomeric binders or monoclonal antibodies11.

Antibodies targeting the hydrophobic stem-helix region prevent the S2 subunit from refolding and pulling viral/host membranes together, effectively freezing the virus in a pre-fusion intermediate2.

Engineered IgM scaffolds or multivalent nanobodies (AMETA) that cross-link Spike trimers (in cis on the same virion or in trans between virions) to aggregate viral particles and prevent membrane fusion2.

Antibodies or compounds that induce premature shedding of S1 and triggering of Spike into the postfusion state in the absence of target membranes, effectively inactivating the virus before it can engage host cells2.

Targeting the hydrogen-bonding interface between CD147 and the Spike RBD "up" conformation to prevent ACE2-independent entry12.

Targeting conserved N-glycosylated asparagine and disulfide-bonding cysteine residues on the Spike protein to destabilize its architecture, lock the RBD in a "down" conformation, and prevent viral entry13.

Block host protease TMPRSS2 to prevent spike priming for membrane fusion1,4,8,10,14-20.

Modulate ACE2 receptor expression, shedding, or availability to reduce viral docking1,3,7,16,17,21,22.

Engineered soluble forms of human ACE2 that act as decoys, competitively binding to the SARS-CoV-2 spike protein. This prevents viral particles from interacting with membrane-bound ACE2 on host cells, effectively blocking viral entry21,23.

Compete with heparan sulfate proteoglycans (HSPGs) to disrupt initial viral attachment5,10,16,24.

Inhibit endosomal protease cathepsin L (alternative pathway for spike activation)1,3,4,8,10,16-21,25.

Block integrin receptors - especially α2β1 (ITGA2) and α5β1, αvβ3 - involved in ACE2-independent entry16,17,26,27.

Blocking or down-regulating cell-surface Neuropilin-1 (NRP1) cuts off an auxiliary SARS-CoV-2 entry route and dampens downstream IL-6-mediated neuroinflammation10,16,17,28,29.

Deplete membrane cholesterol to destabilize lipid raft-dependent entry mechanisms3,5,17,18,30.

Disrupt viral envelopes or spike-receptor interactions via surfactant activity.

Inhibit clathrin-mediated endocytosis or endosomal acidification to prevent viral internalization3,8,17,18.

Block furin-mediated cleavage of the spike protein to impair viral entry1,4,10,16,17.

Blocking host receptor-tyrosine-kinase HER2 prevents spike-triggered signaling and clathrin-mediated uptake, reducing early SARS-CoV-2 entry and downstream replication31,32.

AXL tyrosine-kinase binds the spike N-terminal domain and mediates ACE2-independent entry; knockout or pharmacologic inhibition sharply reduces SARS-CoV-2 infection in pulmonary and bronchial cells10,16,17,27,33.

Monoclonal antibodies block CD147, an inducible receptor upregulated by SARS-CoV-2 via AHR activation. CD147 binds the Spike RBD to facilitate ACE2-independent entry, particularly in ACE2-deficient cells. Blockade prevents viral entry and restores immune homeostasis8,10,12,16,17,27,29,33.

Receptome profiling identifies KREMEN1 (Wnt co-receptor) and ASGR1 (asialoglycoprotein receptor) as functional alternate receptors that enable ACE2-independent entry; antibodies, soluble ectodomains or siRNA can block this route10,16,17,27,33.

C-type lectin receptors DC-SIGN and L-SIGN capture spike glycans to promote attachment; anti-CLR antibodies, glycodendrimers or soluble lectins (griffithsin, cyanovirin-N) competitively block this step10,16,33,34.

HDL-scavenger receptor B type 1 binds spike-HDL complexes and facilitates ACE2-dependent entry; small-molecule SR-B1 antagonists or neutralizing antibodies reduce infection10,16,35.

Targeting members of the T-cell immunoglobulin and mucin domain (TIM) family. In the kidney, Kidney Injury Molecule-1 (KIM-1/TIM-1) acts as an attachment factor for SARS-CoV-2. TIM-1 and TIM-4 can enhance viral infection by binding to phosphatidylserine (PS) on the viral envelope, promoting ACE2-dependent endocytosis16,36.

Endosomal lipid-kinase PIKfyve generates PI(3,5)P₂ required for late-endosome fusion; inhibitors (apilimod, UNI418) block cathepsin-dependent entry across variants10,37,38.

EHMT2 inhibitors diminish lysosomal maturation of cathepsin-L, preventing spike S2' cleavage and endosomal fusion, thereby blocking SARS-CoV-2 entry across ancestral and variant strains39.

Blocking MET tyrosine-kinase disrupts coronavirus internalization and early replication steps, capmatinib shows broad anti-CoV activity in vitro32.

Activation of Nrf2 (e.g., by PB125 or DMF) downregulates ACE2 and TMPRSS2 mRNA, reducing viral docking and spike priming in host cells40.

Blockade of Ca2+-activated TMEM16F lipid-scramblase/ion-channel suppresses spike-driven membrane fusion and triggers antiviral autophagy, yielding multi-log viral reduction in cell and animal models3,10,15,17.

TfR serves as an ACE2-independent entry receptor that can transport SARS-CoV-2 from cell membrane to cytoplasm. Anti-TfR antibodies or competitive peptides can prevent viral entry and reduce pathological lung injury10,16,27,41.

DPP4 serves as a cell surface binding target for the spike protein RBD and can enhance SARS-CoV-2 infection by promoting ACE2 receptor-dependent endocytosis. DPP4 inhibitors may provide dual benefits for COVID-19 patients with diabetes and reduce cytokine storm16,42.

MYH9 acts as a coreceptor that enhances SARS-CoV-2 infection by promoting endocytosis dependent on ACE2, particularly in cells with low ACE2 expression. Inhibition can significantly reduce viral infection16.

Cell surface GRP78 serves as an attachment factor that promotes viral endocytosis by interacting with spike protein and endogenous ACE2. GRP78 also acts as a viral protein chaperone. Small molecule inhibitors show antiviral efficacy16,27,43.

TTYH2 binds to the RBD domain of spike protein similar to ACE2 and contributes to myeloid cell inflammatory responses. Blocking TTYH2 may reduce excessive inflammatory reactions16.

TIM-1 and TIM-4 phosphatidylserine receptors directly interact with PS on SARS-CoV-2 outer leaflet, enhancing viral infection by promoting ACE2-dependent endocytosis. These represent druggable targets for intervention16.

ADAM17 is triggered by spike protein to cleave ACE2, leading to extracellular ACE2 detachment and enhanced host protease activity that promotes viral cytoplasmic fusion1,16.

The Ezrin protein can inhibit viral infection by reducing the expression of key entry receptors like ACE2 and TLRs. Peptides derived from Ezrin have shown potential in inhibiting viral pneumonia16.

The host cell surface receptor LY6E inhibits SARS-CoV-2 infection by interfering with spike protein-mediated membrane fusion and the necessary cytoskeletal rearrangement. Augmenting LY6E function could serve as a defensive therapeutic approach16.

The host protein IFITM3 is an interferon-induced restriction factor that prevents SARS-CoV-2 invasion by regulating host cell membrane fluidity to block the fusion of the viral envelope with the plasma membrane. Enhancing IFITM3 activity is a potential host-directed antiviral strategy16.

C-type lectin receptors that facilitate viral attachment through interaction with spike glycans. Blocking these receptors can reduce viral entry particularly in dendritic cells and macrophages8.

Blocking AAK1-dependent clathrin-mediated endocytosis can reduce viral internalization; baricitinib is a dual JAK/AAK1 inhibitor proposed to impede SARS-CoV-2 entry8,18.

Endo-lysosomal membrane protein TMEM106B regulates lysosome function and cooperates with V-ATPase; required for SARS-CoV-2 infection (facilitates cathepsin/LAMP1+ compartment entry)10,27,37.

ATP6AP1/ATP6V1A subunits acidify endosomes/lysosomes enabling cathepsin-dependent S2' activation and late entry; nsp6 and M interact with these subunits10,34,37,44.

RAB7A with its GEF (Mon1-Ccz1: CCZ1/CCZ1B/C18orf8) and HOPS (VPS39) traffic incoming virions to fusion sites and influence ACE2 surface levels10.

VPS29/VPS35/VPS35L, SNX27 and CCC (CCDC22/CCDC93/COMMDs) drive retrograde recycling; knockout lowers ACE2 surface and blocks entry10,37,45.

ACTR2/ACTR3/ARPC3/ARPC4 and WASHC4 support retromer budding and receptor recycling required for efficient entry10.

AP1B1/AP1G1 support early (TMPRSS2-biased) entry in airway cells by positioning proviral cargos and routes10.

Activated Aryl Hydrocarbon Receptor (AHR) translocates to the nucleus to drive the transcription of CD147 (Basigin), promoting an inducible, ACE2-independent viral entry route. AHR antagonists can prevent this receptor upregulation and limit extended infection12,46,47.

Direct nanoscopy shows SARS-CoV-2 binds tall HS nanoclusters that mediate cell-surface attachment and subsequent endocytic uptake; ACE2 is engaged downstream post-endocytosis24.

Internalized virions reside in vesicles that can contain multiple particles; dynamin inhibition or dominant-negative DNM2 reduces uptake and gene expression; pattern and vesicle size are consistent with macropinocytosis as a major entry route3,17,24,26.

PI4KIIIβ is a host kinase involved in viral entry and replication. It generates phosphatidylinositol 4-phosphate (PI4P), which is essential for regulating lipid membrane composition and trafficking events hijacked by coronaviruses for entry and the formation of replication organelles38.

Blockade of the histamine H1 receptor, a potential alternative receptor for SARS-CoV-2 entry. Antihistamines may also offer immunomodulatory benefits3,21.

Activation of bile acid receptors like FXR and TGR5, which can downregulate ACE2 expression and exert anti-inflammatory effects, thereby reducing both viral entry and immunopathology3.

SARS-CoV-2 variants evolved to use a diverse range of host transmembrane serine proteases (TTSPs) beyond TMPRSS2 for spike protein activation. For example, Alpha and Delta show enhanced binding to Hepsin, while Beta can utilize Kallikrein 13 (KLK13)4,17.

Extracellular vimentin (eVIM) acts as a host attachment factor or co-receptor for SARS-CoV-2, bridging the virus to its primary receptor on the host cell surface. Blocking eVIM with monoclonal antibodies prevents this interaction, thereby inhibiting viral entry48.

Blocking ITGB3, an integrin receptor involved in platelet aggregation and immune cell signaling. ITGB3 plays a role in coagulation abnormalities and immune dysregulation in COVID-19. Inhibition of ITGB3 could mitigate microthrombosis and inflammatory responses26.

Modulating the host circadian clock pathway to reduce ACE2 expression and limit cell-cell fusion. This can be achieved by inhibiting the transcription activator Bmal1 or by using REV-ERB agonists, which repress Bmal1 and downregulate ACE217.

Tubby Like Protein-3 (TULP3) acts as a pivotal adaptor protein that governs the trafficking of ACE2 to the primary cilium axoneme, partially through interaction with the IFT-A complex. TULP3 depletion significantly reduces ciliary ACE2 enrichment and impairs the entry of SARS-CoV-2 variants49.

The presence of ACE2-enriched primary cilia is a determinant of host cell tropism and viral invasio. Genetic perturbation of key ciliogenesis genes, such as IFT88 or ARL13B, leads to deciliation or structural defects that significantly diminish SARS-CoV-2 infectivity in lung and retinal epithelial cells49.

CD169 is a sialic-acid-binding I-type lectin on macrophages and dendritic cells that captures SARS-CoV-2 via the Spike NTD. While macrophage infection is often abortive (leading to RIG-I/MDA-5 inflammation), CD169 facilitates efficient trans-infection to ACE2-expressing cells27.

CLEC4G is a C-type lectin expressed in liver and lymph nodes that binds SARS-CoV-2 Spike NTD and RBD. Soluble CLEC4G or knockdown significantly inhibits viral entry in ACE2-independent pathways27.

LDLRAD3 is a membrane-associated protein and E3 ubiquitin ligase regulator that binds the SARS-CoV-2 Spike NTD with high affinity, and mediates viral entry in neurons and myeloid cells lacking ACE2; soluble LDLRAD3 blocks this pathway27.

TMEM30A, the beta-subunit of the P4-ATPase phospholipid flippase, binds the Spike NTD and facilitates ACE2-independent entry. Loss-of-function studies confirm its necessity for infection in specific ACE2-deficient cell types27.

Lymphocyte Function-Associated Antigen 1 (LFA-1) acts as an alternative receptor mediating SARS-CoV-2 infection in T cells (Jurkat lines and primary CD4+ T cells), contributing to T-cell death and lymphopenia27.

SARS-CoV-2 Spike (RBD and full-length) binds the N-terminal domain of CD4 with high affinity, enabling infection of T-helper cells. Soluble CD4 or neutralizing anti-CD4 antibodies suppress this infection route, which is linked to IL-10 dysregulation27.

Lipid raft-associated gangliosides (e.g., GM1) serve as the primary attachment receptors for the Spike NTD, acting as "electrostatic attractors." This interaction is essential to trigger the conformational change that exposes the RBD for ACE2 binding5.

HDAC6 binds unanchored ubiquitin chains on viral capsids to facilitate physical uncoating through cytoskeletal shear forces. It also regulates innate immune responses18.

Blocking p38 MAPK signaling disrupts virus-induced membrane invagination and endocytosis initiation. The activated p38 signal acts as a trigger for viral internalization, representing a broad-spectrum antiviral target18.

SARS-CoV-2 spike protein activates EGFR to enhance downstream signaling (ERK1/2, AKT) and upregulate survivin; inhibition reduces infection and inflammation19.

SARS-CoV-2 S2 refolding and membrane fusion are calcium-dependent; depleting calcium or blocking calcium interaction promotes reversible conformational changes that inhibit fusion2.

The Nedd8-activating enzyme 1 (NAE1) pathway is required to maintain cellular levels of the host protease TMPRSS2. Inhibition of neddylation triggers the loss of TMPRSS2, preventing spike protein priming, syncytia formation, and viral entry50.

Membrane-bound MUC1 is a hub gene that inhibits ferroptosis and sensitizes cells to Vitamin E alleviation of oxidative injury via the GSK3B pathway. It also provides steric hindrance to pathogen entry51.

SARS-CoV-2 infection activates the Aryl Hydrocarbon Receptor (AHR), which translocates to the nucleus and binds the CD147 promoter, driving the inducible overexpression of CD147. This creates a positive feedback loop for extended viral entry and inflammation12.

The Type-2 cytokine IL-13 significantly downregulates ACE2 mRNA and surface protein expression in human airway epithelial cells. This transcriptional suppression reduces the availability of the viral receptor, thereby inhibiting Spike protein attachment and preventing viral entry22.

Nucleoside analogs interfere with viral RNA synthesis1,3,8,15,16,37.

Bind to allosteric sites on RdRp to disrupt RNA synthesis52.

Blocking Mpro prevents viral polyprotein cleavage and can minimize Mpro-driven mitochondrial dysfunction1,3,8,14-16,21,37,53-56.

Blocking PLpro activity, which processes viral polyproteins and disrupts host immune response1,3,14,57,58.

Inhibiting the viral helicase enzyme needed to unwind RNA for replication3,59.

Inhibit viral RNA capping by targeting nsp10/nsp16 complex.

Targeting the viroporin activity of the small envelope protein that forms pentameric ion channels and is involved in viral assembly and pathogenesis1,3.

Disrupt N protein's RNA binding and oligomerization, preventing genome packaging. N is heavily sialylated in patients and infected cells; NEU1-regulated desialylation enhances N-RNA affinity, so preserving N sialylation further reduces replication3,60-63.

Compounds targeting the disordered N-terminal domain (1-68), central linker region (181-248), or C-terminal domain (370-419) to disrupt RNA binding, liquid-liquid phase separation, and viral genome packaging9,60.

Inhibit assembly of viral structural proteins and RNA into new virions3,64.

Targeting Nsp1, which suppresses host gene expression by blocking mRNA entry into ribosomes and causing host mRNA degradation37.

Small molecules that stabilize or destabilize specific conformations of the disordered linker region between Nsp1 N-terminal and C-terminal domains, modulating its interaction with the ribosome and limiting viral translation inhibition9.

Compounds that mimic or disrupt Cu(II) binding to the disordered region containing key residues W161 and H165, altering Nsp1 structural dynamics and function9.

Blocking the activity of Nsp2, which may play roles in host cell environment modulation and interacts with prohibitin proteins.

Targeting the large multi-domain non-structural protein 3, particularly its macrodomain (Mac1) that suppresses host immune response by removing ADP-ribose modifications, and the ubiquitin-like domain 1 (Ubl1) that mediates important interactions with other viral proteins for replication complex formation18,65.

Disrupting Nsp4's critical role in double-membrane vesicle (DMV) formation and organization of viral replication complexes, which are essential for creating protected environments for viral RNA synthesis18.

Preventing essential protein-protein interactions between components of the viral replication machinery, particularly the interaction between Mpro (Nsp5) and the primase Nsp8, which is critical for the function of the replication-transcription complex.

Counteracting Nsp6's ability to limit autophagosome expansion, which may help the virus evade autophagy-mediated viral clearance44.

Targeting the Nsp7-Nsp8 complex that functions as a primase for RdRp, essential for initiating RNA synthesis37.

Targeting Nsp9, an essential RNA-binding protein required for viral RNA synthesis and replication that functions through both RNA and DNA binding capabilities and potential dimerization. Nsp9 also sequesters let-7b, suppressing TLR7-mediated immunity37,66.

Blocking Nsp10, which serves as an essential cofactor for both Nsp14 (ExoN/N7-MTase) and Nsp16 (2'-O-MTase), thereby disrupting viral RNA processing and immune evasion37,67.

Blocking the multiple enzymatic functions of Nsp13, which possesses RNA helicase, NTPase, and RNA 5'-triphosphatase activities essential for viral replication and mRNA capping37,68.

Targeting the bifunctional nonstructural protein 14 (Nsp14), which contains both N7-methyltransferase (N7-MTase) activity crucial for viral mRNA cap formation and 3'-5' exoribonuclease (ExoN) activity that provides proofreading during RNA replication, reducing mutation rates and maintaining viral genetic fidelity1,36,37,67,69.

Mechanisms that target the viral endoribonuclease Nsp15, which helps SARS-CoV-2 evade host immune detection37,70.

Nsp16 functions as a 2'-O-methyltransferase that methylates the 5' cap of viral RNA, preventing degradation by host cells. Inhibiting this activity can impair viral RNA stability and replication1,16,37,71.

Targeting the RNA packaging signal in the spike protein gene that may facilitate incorporation of genomic RNA into virions.

Inhibiting the ion channel activity of ORF3a, which forms viroporins, induces apoptosis, and activates the NLRP3 inflammasome, contributing to viral pathogenesis and release3,72.

Disruption of the disordered N-terminal region of ORF3a that controls protein localization and retention at the plasma membrane, essential for viral assembly and immune evasion9.

Inhibition of the disordered TRAF-binding region that activates NF-κB and NLRP3 inflammasome pathways, reducing hyperinflammation and cytokine storms9.

Counteracting ORF6's antagonism of interferon signaling and disruption of nuclear transport, which prevents antiviral gene expression through sequestration of import factors.

Blocking ORF7a and ORF7b activities that modulate host immune response and potentially participate in viral assembly through interactions with host proteins and other viral components.

Countering ORF8's interference with MHC-I-dependent antigen presentation and downregulation of interferon responses, which help the virus evade immune detection21.

Preventing ORF9b from suppressing host innate immunity through targeting mitochondria and disrupting MAVS signalosome formation, which impairs interferon responses36.

Blocking the potential roles of ORF10 in viral pathogenesis and replication73.

Small molecules that occupy pockets at the nsp10-nsp14 interface to prevent nsp10-mediated activation of the ExoN proofreading enzyme. Blocking this PPI lowers proofreading and can sensitize SARS-CoV-2 to nucleoside analogs67,69.

Ligands that bind the hinge connecting ExoN and the N7-methyltransferase domain to perturb ExoN conformation/communication and reduce proofreading activity67.

Allosteric or proximal binders that bias the catalytic general base His268 toward the inactive orientation observed crystallographically, suppressing DEDDh ExoN activity and enhancing NA efficacy67.

Ligands for two non-interface allosteric pockets on nsp10 (sites III & IV) that could lead to allosteric inhibitors of nsp10 function or serve as handles for nsp10-directed PROTACs to disable ExoN/MTase cofactor activity67.

Small molecules that bind the conserved coronavirus membrane (M) protein and trap it in non-productive conformations (e.g., stabilize the TM-domain dimer or the Mshort state), preventing Mlong conversion, multimerization, membrane curvature, and virion assembly. Resistance clusters at pocket residues (e.g., Y95, S99, N117, P132), yet conservation across sarbecoviruses suggests broad coverage37,64.

Host E3 ligases FBXO22, ZBTB25 and Parkin can ubiquitinate Mpro/3CLpro and drive its proteasomal degradation; pharmacologic recruitment may lower viral fitness and complement catalytic-site inhibitors54-56.

Membrane-type matrix metalloproteinase-14 (MMP14) selectively binds and cleaves SARS-CoV-2 3CLpro at loop-2 (G170|V171), eliminating protease activity and suppressing viral replication. An engineered zymogen (pro-PL-MMP14) carries a viral PLpro cleavage motif (LxGG) between the pro- and catalytic domains, enabling activation specifically in infected cells55.

Small molecules that occupy the nsp12 catalytic pocket/NTP entry channel and modulate RNA/NTP binding, yielding mixed or competitive inhibition and blocking replication in cells52.

Ligands that bind an allosteric pocket in the Palm subdomain adjacent to the NTP entry channel, inducing noncompetitive inhibition and slowing polymerase catalysis52.

Compounds that dock to an allosteric pocket in the Thumb domain and reduce RdRp processivity; several repurposed/natural products show micromolar inhibition in biochemical assays52.

Super-resolution mapping places nsp5 (Mpro) predominantly inside double-membrane vesicles (DMVs), implying that polyprotein processing proceeds after DMV closure within the DMV lumen. Therapeutic concepts: inhibitors optimized for DMV access; agents that disrupt the Mpro-pore microenvironment37.

Inhibitors developed for Hepatitis C, such as NS5A inhibitors and NS5B polymerase inhibitors, have potential cross-reactivity against SARS-CoV-2 replication machinery3.

Targeting regulatory sites on the papain-like protease (PLpro) outside of the catalytic active site, the interface of the N-terminal ubiquitin-like (Ubl) domain57.

Stabilizing the interaction between the Spike (S) protein cytoplasmic tail and the Membrane (M) protein to enhance S protein retention in the ERGIC. This prevents S protein trafficking to the cell surface, thereby reducing its availability to mediate cell-cell fusion (syncytia formation)17.

The SARS-CoV-2 ORF3a protein binds the host VPS39 subunit of the HOPS complex, blocking autophagosome-lysosome fusion and preventing viral degradation. Small molecules binding the ORF3a cytosolic surface can disrupt this interface to restore autophagic flux and promote lysosomal degradation of viral components72.

Compounds that disrupt the structural zinc-finger motif of PLpro (essential for structural integrity) via metal ejection, intercalation, or coordination, thereby destabilizing the enzyme and inhibiting function58.

The accessory protein ORF3c localizes to mitochondria and alters host metabolism by promoting a shift from glycolysis to fatty acid oxidation and OXPHOS. This increases reactive oxygen species (ROS) and inhibits autophagic flux; targeting ORF3c could restore metabolic homeostasis36.

Inducing viral mutagenesis or depleting nucleotide pools.

Inhibition of IMP dehydrogenase depleting guanosine nucleotides3.

Inhibition of dihydroorotate dehydrogenase depleting pyrimidine nucleotides.

Inhibition of ribonucleotide reductase reducing deoxyribonucleotide pools.

Competitive inhibition of glucose metabolism to limit viral energy sources18,74.

Depletion of asparagine to inhibit viral protein synthesis.

Sequestration of iron to limit availability for viral replication.

Inhibition of S-adenosylmethionine synthesis impairing viral RNA methylation.

Inhibition of glutamine metabolism to reduce nucleotide precursors74.

Reducing cellular cholesterol destabilises lipid rafts, impairs membrane fusion, and disrupts replication-organelle formation, limiting viral entry and assembly. Strategies include HMG-CoA-reductase inhibition and direct extraction of membrane cholesterol10,17,18,30,75.

Disruption of FABP4, a host metabolic protein critical for the formation and function of SARS-CoV-2 replication organelles (double-membrane vesicles)18,76.

Suppressing the neurotrophin receptor TrkA interferes with SARS-CoV-2 RNA replication/assembly, producing multi-log viral reduction even when added hours after infection31.

SARS-CoV-2 depends on the host CDK1-Cyclin B1 complex to complete crucial steps of its replication cycle. Small-molecule CDK inhibitors force a G2/M cell-cycle arrest, sharply reducing viral RNA synthesis and protein production in vitro. Because CDK1 and Cyclin B1 are over-expressed in COVID-19 blood samples, they represent druggable host factors for broad-spectrum antiviral intervention77,78.

Viruses hijack Rho-family GTPases (RhoA, Rac1, Cdc42) and downstream ROCK/PAK/mDia kinases for actin- and microtubule-based trafficking. Inhibitors that block ROCK activity or prevent GTPase prenylation impair endocytosis, replication-organelle formation, and virion egress, and can potentiate innate antiviral signaling30,79.

SARS-CoV-2 reprograms airway-epithelial transcription by activating host chromatin regulators - HDAC1/2/7, NCOR1, KAT2B (GCN5), cohesin (SMC3) and SWI/SNF components (PBRM1, SMARCA4). The resulting histone-acetylation and 3-D chromatin changes suppress interferon genes and create a replication-permissive state. Inhibiting these regulators with HDAC, EZH2 or SWI/SNF modulators restores antiviral transcription and sharply reduces viral yield in vitro3,46,54,56,80.

Blocking the histone H3K9 dimethyltransferase G9a (EHMT2) reverses SARS-CoV-2-driven chromatin silencing and m6A translational re-wiring, while secondarily impairing cathepsin-L maturation; the combined epigenetic effects suppress both viral entry and intracellular replication39,81.

Pharmacologic tuning of the unfolded-protein response (BiP/HSPA5 induction, PERK-eIF2α signaling) restores ER homeostasis, curtails viral protein translation and blocks DMV biogenesis across coronaviruses26.

Shifting cellular metabolism toward catabolism (AMPK) and dampening cap-dependent translation (mTOR blockade) depletes biosynthetic resources, suppressing SARS-CoV-2 RNA and protein output in vitro and in vivo3,18,82.

Stem-loop-binding protein (SLBP) binds the SARS-CoV-2 -1 PRF pseudoknot through its R46/S94 RNA-binding pocket, boosts frameshifting and pp1ab synthesis; CRISPR or small-molecule disruption of SLBP-RNA interaction curtails replication83.

Far-upstream element-binding protein 3 forms RNP complexes with SLBP and ribosomal proteins at the -1 PRF site to raise frameshifting; silencing restricts viral growth83.

These ribosomal proteins co-localise with -1 PRF RNA and, when over-expressed, significantly increase frameshifting; their depletion suppresses replication, identifying them as host translation cofactors commandeered by SARS-CoV-283.

Interferon-induced protein Shiftless competes at the -1 PRF site and lowers frameshifting, acting as an intrinsic restriction factor; boosting SFL or mimicking its mechanism can counter SLBP/FUBP3-mediated enhancement83.

Active SARS-CoV-2 main protease (Mpro) collapses oxidative phosphorylation, depolarizes or hyper-polarizes mitochondria and fragments their network; stabilizing the respiratory chain or blocking Mpro-mediated cleavage of mitochondrial proteins can maintain ATP production and limit virus-induced cell damage8,18,36,53,73,74,84,85.

Suppressing the MAPK/ERK cascade by blocking MAP2K1/2 prevents phosphorylation of N, ORF9b and multiple NSPs, trimming viral RNA synthesis and dampening excess cytokine signaling3,26,32.

Knocking out or destabilizing DYRK1A lowers ACE2/DPP4/ANPEP transcription and blocks double-membrane-vesicle formation, jointly impairing coronavirus entry and early RNA-replication steps32,86.

Stabilize or up-regulate TOM70 to counteract ORF9b-induced MAVS suppression, prevent lactate over-production and maintain antiviral oxidative phosphorylation84.

SARS-CoV-2 infection and pro-inflammatory cytokines drive VDAC1 over-expression, oligomerisation and plasma-membrane mis-targeting. The resulting ATP loss and mtDNA release fuel NLRP3/STING activation and macrophage dysfunction. Small-molecule or biologic VDAC1 blockers restore cellular bioenergetics, dampen chemokine release and correlate with reduced clinical severity85.

SARS-CoV-2 creates a high-flux glycolytic state; blocking the rate-limiting kinase PFKFB3 lowers fructose-2,6-bis-phosphate, curbs viral RNA synthesis, and dampens cytokine release74,78.

Excessive Drp1-driven fission fragments mitochondria, fuels ROS and cytokine surges in COVID-19; Mdivi-1 blocks Drp1 GTPase, restores Δψm and limits inflammation74.

Boost the antiviral stress-granule pathway by up-regulating or mimicking Ras-GAP-SH3-domain-binding proteins-1/2 (G3BP1/2). Reinforced SGs sequester translation factors and viral RNAs, throttling SARS-CoV-2 protein synthesis. Double G3BP1/2 knockout increases viral titres, underscoring their overlapping antiviral role18,54,56,87.

Chelation of the Zn²⁺ catalytic site on host MMPs limits MMP-assisted steps of SARS-CoV-2 replication and dampens downstream tissue damage3,55,88.

Disrupting α/β-tubulin dynamics impairs intracellular trafficking of viral components and lowers lung viral load; orally bio-available agents show potent protection in hamsters3,15,89.

B0AT1 enhances ACE2 stability by assembling it into high-quality heterodimer structures. The ACE2-B0AT1 complex can simultaneously bind two spike proteins, significantly promoting viral recognition and infection1,16.

Blocking the calcineurin-NFAT signaling pathway that is activated by viral Nsp1 through peptidyl-prolyl cis-trans-isomerases, contributing to immune activation1,34.

Enhancing RNF2 expression or function to inhibit coronavirus replication. RNF2 is an E3 ubiquitin ligase that interacts with SARS-CoV-2 nucleocapsid protein and acts as an antiviral host factor. Overexpression reduces viral loads while knockdown increases viral replication60.

Enhancing ARL15 expression or function to inhibit coronavirus replication. ARL15 is a small GTP-binding protein that interacts with SARS-CoV-2 nucleocapsid protein and acts as an antiviral host factor. Overexpression reduces viral loads while knockdown increases viral replication60.

Host sialidase NEU1 removes terminal sialic acids from the coronavirus nucleocapsid (N) protein. Maintaining N sialylation lowers N-RNA binding and curbs replication; cell-permeable NEU1 inhibitors acting in the cytoplasm/lysosome (β-CoVs egress via lysosomes) suppress HCoV-OC43 and SARS-CoV-2 replication in vitro and in vivo61.

PIK3C3/PIK3R4 with VAC14 and WDR81/91 initiate endosomal maturation and early autophagy exploited by SARS-CoV-2 and seasonal HCoVs10.

Conserved coronavirus dependency; early autophagy membrane remodeling supports replication organelle formation10,18.

Master regulators of fatty acid/cholesterol synthesis required for coronavirus replication; disruption limits entry/replication10,35,54.

NPC1/NPC2 move cholesterol from lumen to membrane; required for CoV entry/fusion and trafficking10.

SIGMAR1 interacts with nsp6 and organizes ER lipid microdomains used by positive-strand RNA viruses; modulators impact replication/host responses3,10,44.

Host translation factor leveraged by SARS-CoV-2; inhibition shows potent antiviral activity in vitro and in vivo10,78.

Caspase-6 facilitates coronavirus replication by cleaving nucleocapsid (N) into IFN-antagonist fragments. Genetic knockdown/KO of CASP6 or pharmacologic inhibition reduces N cleavage, restores type-I IFN signaling, and suppresses replication; activity is post-entry and requires an intact IFN pathway62.

SARS-CoV-2 activates AHR, a proviral host factor that suppresses type-I IFN, promotes mucin hypersecretion, and drives inflammatory/metabolic dysregulation; antagonism restores antiviral signaling and may limit fibrosis46,47.

AHR up-regulates TiPARP (PARP7), which supports coronavirus replication; dampening AHR-TiPARP signaling could reduce viral RNA output and restore IFN responses46.

3CLpro cleaves TRMT1 (Q530), and TRMT1 deficiency reduces intracellular viral RNA levels; pharmacologic TRMT1 inhibition may limit replication by depriving the virus of pro-replicative tRNA modifications54.

Predicted host factor PSMB2 (20S proteasome beta subunit) co-clusters with SARS-CoV-2-interacting proteins; inhibiting proteasome activity can impede viral protein turnover/replication and modulate downstream inflammation3,26,34.

Thin dsRNA strands physically link DMVs and can tether DMV clusters to larger bodies; likely acting as conduits for spreading replication sites. Targeting their formation/trafficking could limit RO expansion37.

Large, rounded dsRNA granules lacking nsp3/nsp4 pores but decorated with nsp5/nsp8/nsp10/nsp12/nsp13 suggest phase-separated viral factories. Small-molecule condensate modulators or RNA-protein interface blockers may suppress replication37.

Mpro inhibition induces persistent, multi-layered membrane stacks composed of uncleaved pp1a/pp1ab with nsp3 flanking each layer; MLBs can persist after drug washout and coincide with reinfection. Enhancing selective ER-phagy/MLB turnover or blocking nsp3/4 zippering may improve outcomes37.

IMPase is a key enzyme for both de novo biosynthesis and recycling of cellular inositol. Inhibiting IMPase creates a chokepoint, limiting the availability of inositol and its derivatives (PtdIns, PPIns), which are essential for viral replication organelle formation and other processes hijacked by SARS-CoV-238,90.

Inhibition of dihydrofolate reductase, an enzyme essential for the synthesis of nucleotides, thereby depleting the building blocks required for viral RNA replication3.

Targeting the host BRAF kinase, part of the MAPK/ERK signaling pathway, which can be hijacked by the virus to support its replication cycle. Inhibition may disrupt viral proliferation and modulate host inflammatory responses3.

Blocking the farnesylation (a type of prenylation) of host and potentially viral proteins, which is a critical post-translational modification for their membrane localization and function, thereby disrupting viral replication and assembly3.

Disruption of glycosphingolipid metabolism by inhibiting glucosylceramide synthase, which can alter the composition of lipid rafts and membranes of replication organelles, thereby impairing viral entry and replication3.

Inhibition of GSK-3, a key regulator of numerous cellular processes including inflammation, apoptosis, and metabolism, which can be hijacked by SARS-CoV-2 for replication3,51,91,92.

Blocking the PI3K/AKT/mTOR signaling pathway (specifically targeting PIK3CA), which is crucial for cell survival and autophagy regulation, and may be hijacked by SARS-CoV-2 to promote inflammation3,19.

Inhibition of PARP enzymes, which are involved in DNA repair and inflammatory signaling. PARP inhibitors may exert antiviral effects by modulating the host response and limiting virus-induced cellular stress3.

Inhibition of multiple host cell tyrosine kinases that regulate signaling pathways essential for viral entry, replication, and the induction of pro-inflammatory cytokines3.

Specific host protein domains have been identified as critical for SARS-CoV-2 pro-viral activity, including the COMM (Copper metabolism MURR1) domain, Phox homology (PX) domains, and RNA recognition motifs (RRM). Targeting these domains may disrupt host factor support for viral replication45.

The viral main protease (3CLpro/Mpro) cleaves the host tRNA methyltransferase 1 (TRMT1), which disrupts proper tRNA folding and global protein synthesis. Since viral replication is dependent on the host's translational machinery, pharmacologic inhibition of TRMT1 may limit the resources available for viral protein production56.

Human coronaviruses activate HSF1; HSF1 phosphorylation (e.g., Ser326) drives a stress program that can aid replication and intersect with NF-κB/STAT3; inhibiting HSF1 may blunt viral fitness and inflammatory stress47.

ORF10 hijacks the ZYG11B substrate adaptor to engage the CRL2 E3 ligase complex, increasing its activity to degrade IFT46, which results in ciliary dysfunction73.

Cofilin-1 regulates actin turnover that viruses co-opt for entry, trafficking, and egress; elevated/diagnostic CFL1 supports targeting cofilin-LIMK signaling or actin-endocytosis dynamics to curb replication and temper dysregulated immune-cell motility75.

A host microRNA variant (miR-4485-3p+1) that SARS-CoV-2 induces at 24 hours post-infection. The virus appears to use this isomiR to shut down key host pathways, including the cell cycle, protein translation, and metabolism, helping the virus replicate more effectively. A therapeutic antagomir (inhibitor) could block this isomiR, preventing the virus from hijacking these essential host processes78.

Blocking the host protein Drosha, which is required for efficient SARS-CoV-2 replication. Infection by SARS-CoV-2 induces proteolytic cleavage of full-length Drosha into P140 and P25 isoforms and causes its translocation from the nucleus to the cytoplasm. Ablation of Drosha significantly reduces viral genomic and sub-genomic RNA levels, suggesting a non-canonical, pro-viral role92.

Enhancing the binding of the host COPI complex to the ER retrieval motif in the Spike protein cytoplasmic tail. Increased COPI binding promotes intracellular retention of Spike, reducing its trafficking to the cell surface and subsequent cell-cell fusion (syncytia formation)17.

Vacuole Membrane Protein 1 (VMP1) works in concert with TMEM41B to facilitate the "zippering" of ER membranes, converting them into closed spherical double-membrane vesicles (DMVs) essential for the viral replication organelle18.

HDAC1 is recruited to regulate the acetylation state of viral proteins, which influences nuclear retention and enhances viral replication efficiency18.

Host factors SBDS and SPATA5, involved in ribosome biogenesis, are identified as broad-spectrum host dependency factors required for efficient viral protein synthesis and replication18.

TMEM41B mediates nsp3-nsp4 binding to initiate ER membrane zippering for double-membrane vesicle (DMV) formation. VMP1 is subsequently required to convert these membranes into closed spherical DMVs that serve as viral replication organelles for coronaviruses18.

Disrupting the multivalent interactions, ionic environment, or post-translational modifications (e.g., phosphorylation) that drive the formation of viral replication organelles and inclusion bodies via LLPS. Targeting these "reaction crucibles" can destabilize viral factories18.

HSP90AA1 is a molecular chaperone that ensures proteostasis; its inhibition disrupts SARS-CoV-2 virion assembly, suppresses viral replication, and mitigates virus-induced pyroptosis19,68.

Spike protein enhances viral susceptibility by activating ACE2 phosphorylation, inhibiting its degradation, and promoting exosomal ACE2 propagation, thereby increasing host susceptibility to infection21.

Inhibition of the protein-protein interaction (PPI) between the SARS-CoV-2 Envelope (E) protein's C-terminal PDZ-binding motif (PBM) and the host ZO-1 PDZ2 domain. This interaction disrupts tight junctions, compromises epithelial barriers, and fuels cytokine storms93.

SARS-CoV-2 upregulates DGAT1 expression via SCAP/SREBP-1 signaling to drive de novo lipogenesis in the smooth endoplasmic reticulum. The resulting lipid droplets serve as viral replication platforms and assembly sites. DGAT1 inhibition reduces lipid droplet accumulation and may limit viral replication organelle formation35.

SARS-CoV-2 infection downregulates steroidogenic factor-1 (SF-1/NR5A1) expression. Preserving SF-1 function may protect steroidogenic capacity and reduce virus-induced hypogonadism35.

SARS-CoV-2 triggers host lipid metabolism, inducing the accumulation of lipid droplets and "spirally arranged cisternae" (SAC) derived from the ER. The virus upregulates Srebp1, Dgat-1, and Scarb1 to drive cholesterol uptake and lipogenesis, creating a platform for viral replication. Targeting these pathways disrupts the replication organelle biogenesis35.

SIRT3 is significantly downregulated in SARS-CoV-2 infected cardiomyocytes. As a key mitochondrial NAD+-dependent deacetylase, it regulates oxidative stress and inhibits ferroptosis; restoring SIRT3 activity preserves mitochondrial function and prevents cell death51.

The host DEAD-box RNA helicase DDX3X physically interacts with the SARS-CoV-2 Nucleocapsid to enhance viral dsRNA binding and RNP packaging. DDX3X is also exploited to suppress innate immune signaling. Inhibiting DDX3X helicase activity blocks these pro-viral functions63.

Computational modeling indicates that host HSP70 forms a remarkably rigid and compact complex with the SARS-CoV-2 helicase (NSP13), stabilizing the viral protein. Disrupting this chaperone-client interaction could impair viral replication68.

HSP40 functions as a co-chaperone that binds SARS-CoV-2 NSP13 via specific polar contacts. Targeting this interface may prevent the delivery of the viral helicase to the HSP70 folding machinery68.

FNRA (Integrin alpha-5) is induced by SARS-CoV structural proteins. FNRA localizes to lipid rafts and contributes to the cytoskeletal anchoring and membrane dynamics necessary for efficient viral assembly30.

Distinct from extracellular vimentin involved in entry, intracellular vimentin is upregulated by viral structural proteins and associates with lipid rafts. It facilitates the cytoskeletal remodeling required to support virion morphogenesis and budding at the ERGIC30.

SARS-CoV structural proteins upregulate CDKN1A (p21). p21 regulates the cell cycle; its manipulation arrests cell growth, potentially creating a favorable metabolic environment for viral protein synthesis and assembly30.

Kinesin Family Member 11 (Kif11/Eg5) is a top hub gene in the lung transcriptomic network of SARS-CoV-2 infection and is involved in spindle formation and cell cycle regulation. Dysregulation contributes to pathogenesis, and inhibitors may limit viral propagation or associated tissue damage94.

Aurkb is a key mitotic kinase identified as a central hub gene in infected lung tissue and regulates chromosomal segregation and cytokinesis. High expression correlates with severe COVID-19, suggesting potential for kinase inhibitors to modulate virus-induced cell cycle dysregulation94.

Identified as a top 10 hub gene in SARS-CoV-2 infection, Ube2c is essential for the destruction of mitotic cyclins. Upregulation in severe infection links the ubiquitin-proteasome system to viral manipulation of the host cell cycle94.

Galectin-3 is a beta-galactoside-binding lectin upregulated in the heart and brain during SARS-CoV-2 infection. It facilitates viral attachment, drives pro-inflammatory cytokine secretion (IL-6, TNF-α), promotes fibrosis, and is linked to post-COVID sequelae and cancer risks44.

SARS-CoV-2 NSP6 dysregulates the G1/S cell cycle transition in brain tissue by influencing hub genes CDK2, CCND1, and CCNE1. Targeting these kinases may prevent viral hijacking of the cell cycle and reduce neurodegenerative or proliferative sequelae44.

ATP13A3 is a polyamine transporter and host hub gene that directly interacts with SARS-CoV-2 NSP6 in the brain and heart. Modulating its activity or its interaction with NSP6 may disrupt viral replication organelles and polyamine homeostasis44.

Host restriction factor BST2 tethers nascent virions; priming BST2 expression or blocking viral antagonists (ORF7a, ORF3a, Omicron spike) traps particles on the cell surface, curbing spread18,33,37.

M and S1 accumulate in lysosomes and LAMP1-negative vesicles; clustered, hollow rings indicate high virion load pre-egress. Inhibiting lysosomal exocytosis/vesicle traffic could curb release18,37.

Viruses exploit the host CRM1 (Exportin-1) pathway to transport viral ribonucleoprotein (vRNP) complexes or RNA genomes from the nucleus to the cytoplasm for assembly18.

The NXF1 host system is hijacked for the nuclear export of viral mRNAs; targeting this pathway prevents viral transcripts from reaching the cytoplasm for translation18.

ASM activity leads to the clustering of phosphatidylserine (PS) on the plasma membrane inner leaflet, creating a specific lipid microenvironment or "launching pad" required for efficient viral budding18,89.

nSMase2 regulates membrane lipid composition and curvature. Inhibiting this enzyme disrupts the formation of lipid rafts/microdomains necessary for viral assembly and egress18.

Calcium influx is a critical upstream regulator of extracellular vesicle (EV) release. Blocking this pathway prevents the egress of EVs containing viral RNA/replicons, thereby limiting virion-independent transmission89.

Anti-inflammatory agents target cytokine pathways (IL-1/IL-6/JAK-STAT/TNF-α/complement) or inflammasomes to mitigate excessive inflammation3,7,8,14,23,26,29,34,48,71,85,91,94-98.

Boosting type I/II interferons or upstream sensors (e.g., STING, RIG-I) to stimulate antiviral gene expression8,17,18,47,54,71,91.

Peg-IFN-λ engages IFNLR1 on respiratory epithelium, amplifies local ISGs with minimal systemic inflammation8,47,99.

Promoting T-cell/B-cell activity or passive antibody transfer to target infected cells8,26.

Activating innate immunity via PRRs (TLRs, RIG-I, STING) or antiviral effector mechanisms3,21,71,87,100.

Zinc deficiency correlates with severity. Intracellular zinc availability is buffered by metallothioneins and modulates redox status, antiviral immunity, and viral RNA polymerase function20.

Enhancing antioxidant defenses and potentially inhibiting viral replication.

Additional vitamins, minerals, and cofactors essential for immune cell function and signaling101.

Modulating regulatory immune cells (e.g., Tregs) or checkpoint pathways to balance inflammation.

Inhibition of the neuropeptide Y sub-receptor 1 (NPY-Y1) to modulate inflammatory responses. NPY-Y1 receptor antagonists disrupt the NPY-NPY-Y1 receptor cascade, which shows strong correlations with inflammatory cytokines and VEGF expression, which may help regulate cytokine balance and reduce pulmonary edema associated with severe COVID-19102.

Activating STING to enhance interferon production47,100.

Neutralizing granulocyte-macrophage colony-stimulating factor (GM-CSF) or its receptor blunts monocyte/macrophage-driven cytokine storm and lung injury in severe COVID-19100,103.

Blocking interleukin-17 signaling counters ORF8-mediated IL-17 mimicry and downstream NF-κB activation, reducing neutrophil recruitment and pulmonary damage13,46,47,71,100.

Stabilizing mast cells or neutralizing free IgE to quell IL-4/IL-13-mediated “IgE storm” that accompanies severe COVID-19 in some variants7.

Exogenous butyrate / propionate / acetate activate GPR43/GPR109A, damp NLRP3 inflammasome, expand T-regs and boost type I IFN signaling, thereby curbing lung injury and viral load101.

Blocking the oxysterol-sensing GPCR GPR183 curbs chemotactic recruitment of inflammatory monocytes/macrophages into the airways while sparing early IFN signaling, easing lung inflammation103.

Nebulized rh-GM-CSF re-educates dysregulated lung macrophages, improves gas exchange and promotes viral clearance without provoking cytokine-release syndrome103.

Inhibiting spleen-tyrosine-kinase lowers platelet/neutrophil NET formation and IL-1β/TNF-α surges linked to severe COVID-19, while indirectly easing micro-vascular thrombosis3,26,32,47,104.

Engaging the inhibitory receptor LAIR-1 with polymerized type I collagen down-regulates STAT-1 phosphorylation, curbs JAK/STAT-driven cytokine output and thereby dampens COVID-19 hyper-inflammation96.

Viral IFN responses up-regulate IDO1, driving tryptophan catabolism and immunosuppression; selective IDO1 inhibitors cut kynurenine production and may restore antiviral T-cell function74.

BTK amplifies myeloid NF-κB / NLRP3 signaling; covalent BTK inhibitors curb IL-6 / IL-1β surges and improve survival in SARS-CoV-2-infected mice15,26,47.

Substance-P / NK₁R signaling drives pulmonary oedema and cytokine release; NK₁R antagonists restore fluid balance and damp inflammation in infected hamsters3,15.

Spike protein directly binds TLR4 to enhance viral attachment, increase membrane surface virus concentration, and activate downstream inflammatory signaling, inducing antibacterial-like immune responses. Persistent TLR4 stimulation leads to NK cell exhaustion and long-COVID sequelae16,42,105.

Inhibiting cell-surface NEU1 increases sialylation of innate-immune receptors, dampening TLR activation and cytokine surges; sialidase inhibition has rescued mice from infection-induced cytokine storm, suggesting a route to limit hyper-inflammation in COVID-1961.

MSCs possess potent immunomodulatory and regenerative properties, controlling cytokine storms by enhancing endogenous tissue repair and inhibiting immune system overactivation. They increase lymphocytes and regulatory DCs while lowering IL-6, CRP, IL-8, and TNF levels8.

Acellular therapeutic approach using MSC-derived exosomes that retain immune-modulatory, anti-inflammatory, and regenerative capabilities. They reduce cytokine storms, improve alveolar epithelium permeability, transport mitochondria to alveolar cells, and directly inhibit viral replication8.

Nsp14 binds Tollip (C2 domain), and Tollip over-expression or C2-containing fragments suppress Nsp14-mediated NF-κB activation. Tollip knockdown blunts IFNAR1/IFNGR1 loss during infection, implicating Tollip-guided lysosomal routing. Therapeutic concepts include boosting Tollip's NF-κB-restraining C2-LC3 function while selectively limiting receptor-degradative trafficking69.

AHR skews CD4+ T-cell polarisation (Th17↑, Treg/Tr1 shifts) and dampens antiviral IFN signaling; phase-appropriate AHR modulation can rebalance immunity - antagonism earlier (proviral phase), cautious agonism in hyperinflammation46.

3CLpro cleaves the transcription factor TonEBP, generating fragments that enhance viral replication and suppress IFN-β; preserving TonEBP function can support innate responses54.

Predicted host factor CSF1R maps to marketed kinase inhibitors; dampening CSF1R signaling can reprogram inflammatory monocytes/macrophages and reduce lung inflammation in COVID-193,34.

Fractalkine-CX3CR1 drives neuron-microglia crosstalk and pro-inflammatory recruitment; down-modulation reduces microgliosis and cytokine output in neuroinflammation105.

Inhibition of acetylcholinesterase to increase acetylcholine levels, which can modulate the cholinergic anti-inflammatory pathway, potentially reducing cytokine storm and improving respiratory muscle function3.

Activation of alpha-2 adrenergic receptors, which can produce sedative and anti-inflammatory effects, potentially mitigating hyperinflammation in severe COVID-193.

Utilizing macrolide antibiotics for their secondary immunomodulatory properties, which can dampen excessive inflammatory responses3.

Modulation of the adrenergic system to produce anti-inflammatory effects and potentially alter ACE2 expression or function, thereby reducing the host inflammatory response to infection3.

The viral main protease (3CLpro/Mpro) cleaves the transcription factor TonEBP. The resulting N-terminal fragment translocates to the nucleus and competitively inhibits p65 binding on the IFN-β promoter, suppressing the interferon response. Protecting TonEBP from cleavage may help maintain innate immune signaling56.

Modulating the transcription factor ATF3 to restore immune balance. ATF3 is a stress-responsive transcription factor that enhances STAT1-ISG antiviral programs and reduces NF-κB/TNF-α/IL-6 overexpression47.

Hyperactivated STAT3 amplifies IL-6 signaling, promotes fibrosis, and sustains cytokine storm; dampening STAT3 (or upstream JAKs) reduces inflammatory drive and ACE2 upregulation47,106.

DNA/RNA-sensing (cGAS-STING) and IRF3/7 responses are partly SGK-kinase-dependent; SGK3 inhibition can recalibrate STING-IRF signaling to restore antiviral balance without overshooting inflammation47.

Blocking CD44, the primary receptor for hyaluronan (HA), reduces neutrophil infiltration into the lungs, thereby preventing excessive inflammatory responses and lung tissue damage in COVID-1998.

HA deposition in the lungs interacts with CD44, promoting neutrophil retention and exacerbating inflammation. Targeting HA-CD44 interactions may prevent the formation of a pathogenic HA matrix and reduce lung damage98.

PIGR mediates transcytosis of dimeric IgA/M to mucosa; strong diagnostic performance motivates strategies that boost PIGR or deliver sIgA to reinforce mucosal neutralization at the airway entry portal75.

Downregulated in COVID-19; SERPINA5 regulates serine-protease activity and supports STAT1 phosphorylation/nuclear translocation. Normalizing levels may curb protease-driven tissue damage and improve antiviral responses107.

Inhibition of HSPA8, a key hub protein involved in protein homeostasis and immune response regulation. Dysregulation of HSPA8 in COVID-19 patients contributes to immune dysregulation and viral pathogenesis26.

Inhibition of HSPA9, a protein involved in immune regulation and cell stress responses. HSPA9 is implicated in the regulation of apoptotic pathways and immune modulation during SARS-CoV-2 infection. Targeting HSPA9 could help restore immune homeostasis and reduce viral persistence26.

Inhibition of SRC, a protein involved in immune response regulation, inflammation, and coagulation. SRC plays a central role in immune dysregulation in COVID-1926.

Restoring STAT1 activity to enhance immune responses and inhibit viral replication. Despite transcriptional upregulation, STAT1 is often downregulated in COVID-19, suggesting viral interference in interferon responses26.

Soluble decoy receptors, such as the extracellular domain of TNFR2, that bind to and neutralize tumor necrosis factor (TNF-α). This blocks pro-inflammatory signaling pathways, helping to mitigate the cytokine storm associated with severe COVID-1923.

Soluble forms of the GP130 receptor that specifically bind the IL-6/IL-6R complex. This selectively blocks the pro-inflammatory IL-6 trans-signaling pathway while sparing the anti-inflammatory classical signaling, offering a more targeted approach to dampening IL-6-mediated cytokine storm13,23.

PARP14 is an interferon-stimulated mono-ADP-ribosyltransferase that modifies host and viral proteins to inhibit replication. SARS-CoV-2 Mac1 reverses this activity to evade immunity, preserving PARP14-mediated MARylation enhances viral clearance65.

SARS-CoV-2 infection (via CD147 entry) downregulates BCL2 and upregulates BAX/BAK1, driving apoptosis in CD4+ T cells and B cells. Restoring BCL2 levels or blocking CD147 reverses this lymphopenia and restores adaptive immune competence12,108.

The SARS-CoV-2 Envelope (E) protein binds and activates Toll-like Receptor 1 (TLR1) on myeloid cells, inducing robust pro-inflammatory cytokine production independent of viral entry. Note that M protein binds but does not activate TLR127.

GFPT2, the rate-limiting enzyme of the hexosamine biosynthesis pathway, interacts with MAVS at mitochondria-associated membranes (MAMs) to couple metabolic status with sustained type-I IFN responses. Enhancing GFPT2 activity can boost MAVS-mediated antiviral immunity18.

JAK2 acts as an intermediary in cytokine regulation and STAT phosphorylation; JAK2 deficiency reduces neutrophil infiltration and pro-inflammatory cytokine expression in ARDS19.

Targeting hub genes (OAS2, MX1, IRF7, RSAD2, OASL, IFIT1, IFIT3, ISG15) that are upregulated. These genes show strong diagnostic performance (AUC>0.7 for COVID-19) and correlate with neutrophil and Th17 cell infiltration71.

The OAS family genes (OAS1, OAS2, OAS3, OASL) are key ISGs that activate RNase L to degrade viral RNA. Dysregulated OAS activity contributes to both antiviral defense and autoimmune pathology71.

MX1 is a hub ISG with strong antiviral activity against multiple RNA viruses including SARS-CoV-2. Elevated in COVID-19 nasopharyngeal epithelium, MX1 upregulation correlates with disease severity and immune cell infiltration71.

IRF7 is a master transcriptional regulator of type I interferon responses and a validated hub gene in COVID-19. IRF7 upregulation drives ISG expression cascades; its dysregulation contributes to both inadequate early antiviral responses and later immunopathology71.

RSAD2/Viperin is an ISG that inhibits viral replication by disrupting lipid rafts and viral budding. Identified as a hub gene upregulated in COVID-19 epithelial cells, RSAD2 represents both an antiviral defense mechanism and a marker of interferon pathway activation71.

IFIT1 and IFIT3 are ISGs that inhibit viral protein translation by binding viral RNA lacking 2'-O-methylation. Both are hub genes showing high diagnostic accuracy. Their expression correlates with neutrophil and Th17 infiltration71.

LSD1 inhibitors specifically suppress inflammation while preserving IFN-mediated antiviral activity. DDP38003 blocked viral release via the lysosomal acidification pathway and enhanced IFN-independent antiviral mechanisms, balancing inflammation control with antiviral effects in K18-hACE2 mice21.

Circulating galectin-9 has immunomodulatory properties and binds specifically to the host ACE2 receptor. Recombinant humanized gal-9 significantly alleviated acute-phase lethal infection in K18-hACE2 mice21.

Alveolar Type II (ATII) cells produce surfactant lipids, specifically palmitoyl-oleoyl-phosphatidylglycerol (POPG), which normally antagonize TLR4. SARS-CoV-2 induces ATII apoptosis, depleting POPG and releasing the brake on TLR4-driven hyperinflammation. Surfactant replacement restores this inhibition42.

PTP4A3 is a dual-specificity phosphatase upregulated in the lungs during lethal COVID-19. It acts as a critical upstream regulator of the inflammatory response by modulating STAT3 phosphorylation, NF-κB activation, and NLRP3 inflammasome assembly. Inhibition mitigates cytokine storm, reduces macrophage infiltration, and preserves lung parenchymal integrity106.

Modulating antibody Fc domains to enhance effector functions (ADCC/ADCP). Afucosylation increases FcγRIIIa affinity, while specific mutations boost Fc receptor binding to improve clearance of infected cells2.

Fibroblast Growth Factor Receptor 1 (FGFR1) signaling activates the downstream MEK/ERK pathway to suppress the host innate immune response (type I interferon). Inhibiting FGFR1 relieves this suppression, enhancing the expression of IFN-β and interferon-stimulated genes to restrict viral replication50.

CD59 is a lipid-raft associated GPI-anchored protein upregulated by viral structural proteins. It inhibits the complement membrane attack complex (MAC). The virus may exploit CD59 to prevent complement-mediated lysis of infected cells; blocking may enhance immune clearance30.

ZBP1 is a robustly upregulated innate immune sensor that detects viral Z-RNA, and drives inflammatory cell death (PANoptosis) and lung inflammation. Modulating ZBP1 sensing can influence viral clearance and the severity of immunopathology94.

Transforming Growth Factor Beta 1 (TGFB1) and its receptor (TGFBR2) are identified as central hub genes in the heart and lung transcriptomes of infected patients. They drive pathological fibrosis, immune suppression, and epithelial-mesenchymal transition44.

SARS-CoV-2 infection disrupts cell-cell communication networks, specifically inducing abnormal interactions between M2 macrophages and AT2/CD8+ T cells that drive immunosuppression. Blocking the CD147-Spike axis restores homeostatic macrophage communication12.

Inhibiting the interaction between CD47 and SIRPα on blood and immune cells. Blockade enhances the phagocytosis of infected cells and RBCs, potentially reducing thrombosis and stroke risk13.

Re-establish eubiotic taxa (e.g. Dolosigranulum sp., Lachnospiraceae, Propionibacteriaceae) to enhance local SCFA and vitamin B12/K output, reinforce mucin glycosylation and prime MAIT-cell / dendritic-cell antiviral responses46,101.

Specific probiotic strains (e.g., Lactobacillus paracasei F19) produce bioactive lipids (like palmitoylethanolamide) or peptides that block TLR4 signaling and downstream NLRP3 inflammasome activation, reducing lung injury and cytokine release42.

Preventing microthrombi formation in severe cases3,26,107.

Reducing platelet aggregation to prevent clots3,26,75,109.

Inhibit thrombin activity to prevent fibrin formation107.

Directly inhibit factor Xa to reduce thrombin generation.

Enhance antithrombin-mediated inhibition of factor Xa.

Inhibit synthesis of vitamin K-dependent clotting factors.

Block ADP-induced platelet activation and aggregation.

Prevent fibrinogen binding and platelet cross-linking13.

Increase cAMP levels, reducing platelet activation.

Inhibit thrombin-induced platelet aggregation.

Lyse existing thrombi by converting plasminogen to plasmin107.

Supplement antithrombin to enhance anticoagulation.

Exert anticoagulant effects similar to heparin.

Agents that obstruct extracellular NSP3 binding to fibrinogen, normalizing fibrin formation and mitigating virus-driven hyper-coagulation109,110.

Monoclonal antibodies or engineered Fc fragments that block IgG engagement of platelet FcγRIIa, preventing afucosylated IgG-driven platelet activation and thrombus formation104.

SSRIs decrease intraplatelet serotonin; 5-HT₂/5-HT₃ antagonists blunt serotonin-amplified aggregation, collectively reducing COVID-19-associated thrombosis3,104.

SARS-CoV-2 ORF7a activates Weibel-Palade body exocytosis, unleashing ultralarge VWF multimers that enhance platelet adhesion and accelerate thrombus formation. Therapeutic focus: restore ADAMTS-13/VWF balance or block VWF-platelet binding37,107,109,111.

Boost the endogenous inhibitor of the TF-FVIIa complex to damp extrinsic coagulation drive implicated in COVID-19 CCC dysregulation107.

Enhance the thrombin-thrombomodulin-protein C axis to neutralize prothrombotic signaling while preserving anticoagulant and anti-inflammatory effects107.

Restore impaired natural anticoagulant circuits noted among CCC hubs (PROC, SERPINC1), aiming to reduce microthrombi and immunothrombosis107.

Upregulated FGB/FGG associate with excessive fibrin formation and possible profibrotic TGF-β crosstalk; moderating polymerization may reduce microvascular obstruction and downstream fibrosis107.

Meta-analysis shows F2 downregulation; careful, context-specific normalization may restore hemostatic balance while avoiding prothrombotic overshoot107.

As a CCC hub, SERPINF2 (plasmin inhibitor) modulation could re-balance fibrinolysis vs. thrombosis in COVID-associated coagulopathy107.

The membrane protein CD36 acts as a specific receptor for the SARS-CoV-2 Envelope (E) protein on platelets. This interaction triggers p38 MAPK and NF-κB signaling, leading to platelet activation and thrombosis27.

Spike protein activates platelets via TLR4 (and ACE2/TMPRSS2), triggering granule release, thrombin generation, and NET formation. Thrombin creates a feedback loop by enhancing TLR4 surface expression on platelets via PAR1/PAR4-mediated calcium mobilization and calpain activation42.

Enhancing host antioxidant, anti-inflammatory and antiviral defences by activating transcription-factor Nrf2. Upregulates phase-II enzymes (HO-1, NQO1, TRXR), suppresses NF-κB, tempers STING-driven IFN-I output, and downregulates entry factors ACE2/TMPRSS240,41,47.

Reducing inflammation and vascular leakage. Excess MMP-9 promotes lung barrier breakdown and cytokine storm; selective or broad-spectrum MMP inhibitors blunt this damage77,108.

Suppressing prostaglandin-mediated inflammation3,46,95.

Inhibition of pro-inflammatory transcription factor NF-κB (specifically the RELA/p65 subunit) to reduce cytokine production and viral replication19,47,75,94,105,106,111,112.

Neutralizing reactive oxygen species to prevent oxidative damage.

Boosting endogenous glutathione synthesis or regeneration21.

Selective blockade of caspase-1 activation downstream of NLRP1/10 mitigates IL-1β release and pyroptotic damage in infected airway cells, complementing NLRP3-directed approaches54,56.

Blocking NLRP3 activation to reduce inflammatory cytokine release71,85,106,112,113.

Mimicking superoxide dismutase to neutralize superoxide radicals.

Inducing the Nrf2-dependent enzyme HO-1 yields CO, biliverdin and bilirubin, providing antioxidant, cytoprotective and broad antiviral effects that limit viral replication and lung injury40,47.

SIRT1 deacetylates the NF-κB p65 subunit to suppress cytokine storms (IL-6, TNF-α), stabilizes Nrf2 to combat oxidative stress, and regulates ACE2 expression. In the acute phase, SIRT1 activation dampens hyperinflammation and endothelial dysfunction, while in recovery it promotes mitochondrial homeostasis and tissue repair114.

Activating PPAR-γ to suppress pro-inflammatory signaling75.

Blocking iron-dependent lipid peroxidation cell death pathways activated during SARS-CoV-2 infection, which may contribute to tissue damage particularly in the lungs. This approach targets the GPX4/GSH antioxidant system, iron metabolism regulation, and lipid peroxidation processes41,51,115.

Targeting the host cytoskeletal adaptor protein vinculin (VCL) and its interaction with ICAM-1 to reinforce VE-cadherin-actin junctions, suppress excessive leukocyte adhesion, and seal gaps in the alveolo-vascular barrier, thereby diminishing inflammatory exudation and lung edema seen in COVID-19116.

Small-molecule or lipid-A analogues that prevent spike-S1 engagement of toll-like receptor-4, dampening early MyD88→NF-κB cytokine release and subsequent hyper-inflammation16,100,105,108,112.

Small molecules or peptides that prevent GSDMD cleavage/oligomerisation may stop pyroptotic pore formation, lowering IL-1β release and the downstream cytokine-storm cascade54,56,103,112.

Inhibition of Gasdermin-E (GSDME) activation to prevent the pyroptotic cell death of multinucleated syncytia. Blocking this pathway may reduce the release of inflammatory mediators from fused cells and limit subsequent tissue damage17.

Block hypoxia-driven metabolic re-programming that fuels NET formation and cytokine surges in severe COVID-193,47,82,84,108.

Interrupt AGE/RAGE signaling linked to TNF-α amplification and endothelial dysfunction in advanced disease84.

Antagonists of endothelial GPR4 blunt leukocyte adhesion, chemokine/cytokine release and COX-2 induction, thereby mitigating cytokine-storm-driven lung injury95.

Neutralizing the chemokine CXCL10 (also called IP-10) or inhibiting its receptor CXCR3 limits the chemo-attraction of activated T cells and monocytes into lung tissue, tempering the hyper-inflammation and tissue damage seen in severe COVID-1994,97,106.

Eicosapentaenoic and docosahexaenoic acids give rise to resolvins/protectins that improve resolution of post-viral lung inflammation and may lessen long-COVID pathology74.

Inhibiting the MAPK cascade downstream of spike-TLR signaling suppresses NLRP3 activation and cytokine release in lung epithelium, minimizing post-COVID inflammatory damage15,47,69,75,113.

Physical removal of excessive cytokines from blood using adsorption columns to rapidly reduce cytokine storm severity in critically ill patients8.

AHR activation in airway epithelium drives goblet-cell differentiation and MUC5AC/MUC5B expression with mucus hypersecretion; AHR modulation can normalise mucus output and airflow46,47.

3CLpro cleaves NLRP12, a negative regulator of NLRP3, thereby amplifying cytokine production; preserving NLRP12 function may temper hyperinflammation56.

Blocking endothelial/platelet P-selectin binding to SELPLG (PSGL-1) limits rolling/adhesion and immune-cell influx into inflamed tissues105.

Blocking the action of leukotrienes, which are inflammatory mediators involved in the pathogenesis of ARDS. This may help reduce lung inflammation and tissue damage3.

Blocking VEGF signaling to reduce virus-induced angiogenesis, vascular permeability, and pulmonary edema associated with severe ARDS3.

The main protease (3CLpro/Mpro) cleaves NLRP12, a negative regulator of the NLRP3 inflammasome and NF-κB signaling. By disabling this immune checkpoint, the virus can dysregulate the inflammatory response. Preserving NLRP12 function may help temper hyperinflammation56.

Neutralize IL-18 or block IL-18R to minimize inflammasome-driven lung inflammation and pyroptosis112.

Reduce ROS that prime/activate NLRP3 and amplify IL-18112.

Block caspase-1 to curb processing of pro-IL-18/pro-IL-1β and downstream pyroptosis112.

SERPINA3 is an acute-phase serine-protease inhibitor. Augmenting SERPINA3 activity could help restrain neutrophil/chymase proteolysis and downstream inflammation75.

Inhibiting the stabilization of TP53 (p53) that occurs following spike-mediated cell-cell fusion. This stabilization is linked to pro-inflammatory cytokine release and cellular senescence, so its blockade may reduce syncytia-driven pathology17.

Blocking the activation of cleaved caspase-3 in infected astrocytes. This pathological apoptosis is driven by a pro-inflammatory response and contributes to cell death and neuroinflammation29.

SARS-CoV-2 lowers astrocyte EAAT1 (GLAST) and EAAT2 (GLT-1), impairing glutamate uptake and creating neuroinflammation/headache/brain fog. Boosting EAAT1/2 restores synaptic glutamate clearance and dampens downstream cytokines29.

Restoring AKT1 signaling, which is significantly downregulated in severe COVID-19, to reduce neutrophil recruitment, prevent acute lung injury, and support BCL2-mediated lymphocyte survival108.

Downregulating Intercellular Adhesion Molecule 1 (ICAM-1), which is overexpressed during cytokine storms, to reduce endothelial damage and leukocyte infiltration into lung tissue108.

The H2 blocker famotidine is identified as a top compound interacting with ferroptosis-related genes in COVID-19 cardiac tissue. Beyond acid suppression, it may reduce oxidative stress, maintain cardiac stem cell populations, and decrease cytokine release51.

Peroxisome Proliferator Activated Receptor Alpha (PPARA) is identified as a central hub gene in COVID-19 heart tissue involved in lipid metabolism. Its downregulation correlates with ferroptosis and cardiac injury; agonists may restore metabolic homeostasis and inhibit inflammation51.

PRC1 is a microtubule-associated protein and hub gene dysregulated in COVID-19. Transcriptomic analysis links its expression to lung fibrosis disorders (e.g., silicosis), suggesting it contributes to the fibrotic sequelae of severe SARS-CoV-2 infection94.

Transcriptomic enrichment shows significant upregulation of the cellular senescence pathway, specifically the marker CDKN2A (p16), in infected lungs. Senescent cells secrete pro-inflammatory factors (SASP); senolytics could mitigate this chronic inflammatory drive94.

Targeting Tumor Necrosis Factor Receptor 1 (TNFR1), which is significantly upregulated in SARS-CoV-2 associated myocarditis. Excessive TNFR1 signaling drives oxidative stress, endothelial dysfunction, and necroinflammatory lesions; blocking this pathway may prevent the transition to chronic myocardial injury36.

Targeting the chemokine CXCL16, identified as a key biomarker in COVID-19 associated acute kidney injury (AKI) that correlates with immunometabolic collapse and severity. Inhibition of the CXCL16/CXCR6 axis may limit renal inflammation and tissue damage36.

ACSL4 enriches cellular membranes with long-chain polyunsaturated fatty acids (PUFAs), which are the primary substrates for lipid peroxidation. The Spike protein triggers the ferroptotic pathway where ACSL4 facilitates the formation of toxic lipid-ROS; inhibiting ACSL4 prevents the execution of ferroptosis41.

GPx4 is the primary enzymatic "brake" on ferroptosis, reducing toxic lipid hydroperoxides to alcohols. Spike protein exposure disrupts GPx4 levels in a brain-region-specific manner. Preserving GPx4 activity or selenium levels is critical to preventing Spike-induced neurodegeneration41.

SARS-CoV-2 binding degrades ACE2, leading to Angiotensin II accumulation. Ang II activates AT1R, stimulating NADPH oxidase (NOX) to produce ROS, which drives lipid peroxidation and ferroptosis. Blocking this axis mitigates the oxidative cascade triggered by Spike-ACE2 interaction41.

Blocking complement components to reduce inflammation75.

Inhibition of C3 to prevent downstream complement activation75,107.

Monoclonal antibodies that bind complement factor C2 prevent C3 pro-convertase assembly, selectively shutting down classical and lectin amplification while sparing the alternative pathway.

Blocking C1 esterase or C1s to suppress classical pathway activation34.

Targeting C5a or its receptor to reduce inflammatory anaphylatoxin effects104.

Inhibiting Factor B to disrupt alternative pathway amplification.

Blocking Factor D to halt alternative pathway activation.

Targeting MASP-2 to inhibit lectin pathway initiation.

Fusion protein to inhibit complement at sites of activation.

Recombinant soluble complement receptor 1 (sCR1) for multi-pathway suppression.

Neutralizing C3a or antagonizing C3aR diminishes complement-induced platelet activation and microvascular thrombosis104.

Triggering programmed cell death in infected cells via Bcl-2 inhibition3,29,94.

Activating TRAIL death receptors to induce apoptosis in infected cells.

Stimulating Fas receptors to trigger caspase-dependent cell death.

Promoting apoptosis by antagonizing inhibitor of apoptosis proteins (IAPs).

Restoring p53 activity to induce apoptosis in infected cells17,54,56.

Enhancing mTOR-independent/AMPK-mediated degradation of viral components.

Promoting phagocytic clearance of apoptotic cells containing viral material.

Inducing apoptosis with enhanced antigen presentation for immune clearance.

Boost clearance of damaged mitochondria via PINK1/Parkin to lower mtROS and downstream inflammatory signaling84.

3CLpro cleaves p62/SQSTM1 (Q354), NBR1 (Q353, in PEDV) and Galectin-8 (Q158), blocking selective autophagic clearance of viral proteins. Preserving these receptors or enhancing their cargo-linking restores virophagy54.

The viral main protease (3CLpro/Mpro) cleaves the autophagy receptor p62/SQSTM1 at Q354. This disables p62's ability to traffic viral proteins (like the M protein) to autophagosomes for degradation, thus protecting virion components and ensuring successful assembly. Protecting p62 from cleavage could restore this host defense mechanism56.

MCL1 is an anti-apoptotic protein found to be upregulated and raft-associated during viral protein expression. Induction of MCL1 likely delays host cell apoptosis to prolong the window for viral replication and assembly. Inhibition could restore apoptotic clearance of infected cells30.

Exogenous Ang(1-7) or small-molecule Mas agonists restore the protective ACE2-Ang(1-7)-Mas arm of RAAS that is lost after spike-induced ACE2 internalisation, delivering vasodilatory, anti-thrombotic, anti-fibrotic and anti-inflammatory effects that can mitigate ARDS, endothelial dysfunction and long-COVID sequelae111.

Pegylated arginase I lowers extracellular arginine, reducing NO-driven hyper-inflammation and starving viral polyamine synthesis pathways implicated in severe COVID-1974.

Blocking polyamine synthesis pathways that viruses exploit for replication. SARS-CoV-2 requires polyamines for RNA synthesis and protein translation8,68.

Predicted host factor MTR links one-carbon metabolism to SAM availability for viral RNA capping/methylation; modulating the B12-MTR cycle may perturb pro-viral methyl flux34.

BTD is a plasma enzyme that recycles biotin; research identifies BTD as a top diagnostic biomarker and shows pathway enrichment in biotin metabolism, suggesting a nutrient-immune axis worth targeting75.

Targeting APOE, which is involved in lipid metabolism and immune regulation. APOE modulates blood coagulation and immune response26.

Inhibition of APP, which interacts with APOE and plays a role in neuroinflammation and immune dysregulation in COVID-19 patients. APP-targeting strategies could help mitigate immune and systemic disturbances in both acute and long COVID26,44.

PLP (the active form of Vitamin B6) is a top metabolite linked to ferroptosis-related genes. It alleviates myocardial injury by inhibiting ferroptosis and apoptosis, specifically through the activation of the Nrf2 antioxidant pathway51.

SARS-CoV-2 S1 protein acts as a seed for the aggregation of ⍺-synuclein and the hyperphosphorylation of tau (p-tau) in the hippocampus, contributing to neuronal cell death and cognitive decline82.

SARS-CoV-2 S1 protein downregulates critical synaptic plasticity genes, including GRIN2A (NMDA receptor subunit), JPH3, and SHANK1, via HIF-1⍺ stabilization. Restoring the expression of these genes prevents dendritic collapse and rescues cognitive function82.

SARS-CoV-2 S1 promotes the SUMOylation of HIF-1⍺, leading to its stabilization under normoxic conditions in the brain. Blocking this SUMOylation pathway facilitates HIF-1⍺ degradation and protects against synaptic dysfunction82.

MT2A is a cysteine-rich, intracellular zinc-buffering protein that links zinc dysregulation to redox signaling and immunopathology. High MT2A expression in myeloid cells correlates with COVID-19 mortality and co-regulates with viral entry factors and inflammatory cytokines. Targeting MT2A may restore zinc-dependent immune signaling thresholds20.

DMT1 mediates the cellular uptake of ferrous iron. The SARS-CoV-2 Spike protein S1 subunit significantly upregulates DMT1, driving an expanded labile iron pool, oxidative stress, and subsequent ferroptosis in neuronal tissues41.

FPN1 is the only known mammalian cellular iron exporter. Spike protein exposure alters FPN1 expression in the brain as a potential compensatory response to iron overload. Enhancing or stabilizing FPN1 function facilitates iron efflux and prevents ferroptotic cell death41.

Blocking the direct interaction between SARS-CoV-2 Spike protein (via Asn/Cys residues) and host hemoglobin, which disrupts hemoglobin structure/function and contributes to hypoxia and RBC damage13.

Blocking viral proteins that suppress host immunity.

Disrupt ORF9b binding to the C-terminus of TOM70 to restore HSP90-mediated MAVS signaling, type-I interferon output and balanced mitochondrial metabolism26,84.

Countering viral antagonism of STAT1/IRF pathways to reinstate endogenous interferon responses26,46,47,54,56,62,69,71,73,84.

Blocking NSP3's immune evasion via deubiquitinase activity58.

Small molecules or peptides that block NSP3-mediated de-ISGylation of IFIT5, restoring ISG15-dependent IRF3/NF-κB signaling and type I-IFN output110.

Neutralizing ORF6-mediated interferon suppression84.

Preventing NSP1 from blocking host translation.

SARS-CoV-2 activates Wnt / β-catenin signaling to deplete peroxisomes and blunt MAVS-mediated type I/III IFN production. Small-molecule Wnt/β-catenin antagonists reverse this immune-evasion tactic by restoring peroxisome biogenesis, amplifying innate IFN responses and sharply lowering viral replication in airway cells and mouse lungs117.

SARS-CoV-2 Nsp9 binds let-7b, loads it into AGO2, and blocks its packaging into exosomes, sharply lowering extracellular let-7b that would otherwise activate TLR7 and drive type-I interferon/cytokine induction. Countermeasures aim to disrupt the Nsp9-let-7b interface or supply exogenous let-7b to restore TLR7 antiviral signaling66.

Small molecules or peptides that occupy the NTF2-groove of G3BP1/2 or mask N residues I15-G18, preventing N-mediated stress-granule dissolution and restoring PKR/IFN signaling87.

SARS-CoV-2 Nsp14 reduces surface IFNAR1 and IFNGR1 through a lysosomal pathway, blunting IFN-α/β and IFN-γ signaling. Effects are evident in infected cells and with Nsp14 expression; IFNAR2 is spared. Countermeasures aim to preserve receptor abundance or block lysosomal routing69.

Nsp14 augments NF-κB and activates ERK, JNK and p38 MAPKs, promoting cytokine output (IL-1β, IL-6, IL-10, CXCL10/CCL4/CCL5). ExoN-dead mutants largely retain activity, whereas N7-MTase-dead mutants lose it. Targeting Nsp14's MTase function or downstream kinases can curb this pro-inflammatory signaling69.

During infection, activated caspase-6 cleaves N; resulting fragments dampen IRF3/IFN-I signaling and aid replication. Lowering CASP6 abundance (mRNA destabilisation) or inhibiting its activity reduces cleaved-N, reverses IFN suppression, and limits viral growth62.

The SARS-CoV-2 main protease (3CLpro/Mpro) dismantles the RIG-I-like receptor (RLR) pathway by cleaving RIG-I, promoting MAVS degradation, and cleaving the essential adaptor NEMO. This collective antagonism suppresses type I interferon production. Therapeutics may protect these components or otherwise restore the pathway's function54,56.

Activation of the evolutionarily conserved Hippo signaling pathway, which contributes to the host's intrinsic antiviral response during SARS-CoV-2 infection91.

SARS-CoV-2 Nsp5 increases SUMOylation of MAVS, boosting NF-κB signaling; disrupting SUMOylation or enhancing de-SUMOylation can restore balanced IFN/NF-κB responses47.

ORF10 remodels host transcription with reduced oxidative phosphorylation and suppression of interferon/stress-response genes, weakening antiviral signaling. Therapeutic approaches aim to restore IFN/MAVS activity and mitochondrial tone alongside direct ORF10 blockade73.

The Nsp3 macrodomain (Mac1) removes mono-ADP-ribose (MAR) modifications from host proteins (catalyzed largely by PARP14), thereby reversing the host interferon-induced antiviral response. Small-molecule inhibition of Mac1 restores these immune marks, potentiates the innate immune response, and limits viral replication in vivo65.

Blocking the Fc-gamma receptor I (FcγRI) to prevent antibody-mediated, ACE2-independent cell-cell fusion (syncytia formation). This pathway can be triggered by certain anti-RBD antibodies and is implicated in antibody-dependent enhancement (ADE) and the formation of macrophage syncytia17.

Enhancing the activity of interferon-induced transmembrane protein 1 (IFITM1), which is localized at the plasma membrane and exhibits a strong inhibitory effect on spike-mediated cell-cell fusion (syncytia formation), likely by modifying membrane rigidity17.

Antimicrobial peptides with potential antiviral effects.

Peptides blocking viral fusion with host membranes.

Iron-binding protein with antiviral properties.

Antimicrobial peptide disrupting viral envelopes.

Liver-produced peptide with immunomodulatory effects.

Cell-penetrating peptides disrupting viral assembly.

Synthetic 15-25-aa peptides designed in silico that bind conserved spike-RBD or S1/S2 motifs, out-compete ACE2, curb multivariant infection, and blunt pro-inflammatory cytokines110.

Small interfering RNAs targeting viral genes.

Silencing spike gene to prevent viral entry.

Inhibiting nucleocapsid gene to disrupt virion formation.

Sustained gene silencing via short hairpin RNA.

Using microRNAs to target viral RNA degradation.

Use of miRNA mimics or inhibitors to regulate host gene expression and immune pathways, enhancing antiviral responses or suppressing viral replication. Specific miRNAs (e.g., miR-181, miR-874, miR-155, miR-27a) can amplify innate immune signaling or induce apoptosis in infected cells, while inhibition of others (e.g., miR-1290, miR-576) reduces viral replication or virus-induced damage66,78,118.

Silencing the ORF10 gene, whose transcript is highly structured and conserved. A synonymous change that perturbs ORF10 RNA structural dynamics is associated with milder COVID-19, implicating a functional RNA role independent of the protein; targeting the RNA should attenuate ORF10-linked virulence programs73.

MicroRNA-492 is identified as a specific regulator in severe COVID-19 and acute kidney injury (AKI). Modulating its activity represents a potential therapeutic avenue for treating severe renal complications36.