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Budesonide Meta
Colchicine Meta Nigella Sativa Meta
Conv. Plasma Meta Nitazoxanide Meta
Curcumin Meta PPIs Meta
Fluvoxamine Meta Quercetin Meta
Hydroxychlor.. Meta
Ivermectin Meta
Thermotherapy Meta
Melatonin Meta
Metformin Meta

COVID-19 treatment: systemic agents

• Many systemic agents reduce risk

We do not provide medical advice. No treatment is 100% effective, and all may have side effects. Protocols combine multiple treatments. Consult a qualified physician for personalized risk/benefit analysis.
Over 9,000 compounds predicted to reduce COVID-19 risk. SARS-CoV-2 is easily disabled. SARS-CoV-2 infection and replication involves a complex interplay of over 200 host and viral proteins and other factors1-8, providing many therapeutic targets. Scientists have identified 9,694+ compounds9 potentially beneficial for COVID-19. Hundreds of compounds inhibit SARS-CoV-2 in vitro, including many with known pharmacokinetics and proven safety.
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Efficacy confidence - Low-cost systemic agents
Hydroxychloroquinep<0.0000000001
Ivermectinp<0.0000000001
Metforminp<0.0000000001
Curcuminp=0.000000006
Melatoninp=0.00000001
Antiandrogensp=0.00000006
Azvudinep=0.0000001
Colchicinep=0.0000002
Probioticsp=0.000001
N-acetylcysteinep=0.00003
Antihistamine H1RAsp=0.00007
Fluvoxaminep=0.0001
Nigella Sativap=0.0002
Famotidinep=0.0003
TMPRSS2 inhibitorsp=0.0007
Quercetinp=0.002
Efficacy confirmed March 2020 (HCQ)(a),10
P-values indicate the confidence that studies show a significant effect. p=0.05 is the typical threshold for significance in scientific papers, with lower values indicating higher confidence. These treatments show lower risk for COVID-19. See the individual analyses for details of efficacy for specific outcomes and conditions.
Low-cost systemic treatments. Many low-cost treatments have been identified as effective11-1024, including ivermectin, hydroxychloroquine, metformin, antiandrogens, antihistamine H1RAs, TMPRSS2 inhibitors, curcumin, melatonin, colchicine, probiotics, azvudine, N-acetylcysteine, fluvoxamine, nigella sativa, famotidine, and quercetin.
if you say anything in favor of ivermectin you will be cast out of civilization and thrown into the circle of social hell..
Scott Alexander1025
Politicization. Hydroxychloroquine and ivermectin have become the most politicized treatments of all time. As Scott Alexander said1025: "if you say anything in favor of ivermectin you will be cast out of civilization and thrown into the circle of social hell reserved for Klan members and 1/6 insurrectionists. All the health officials in the world will shout 'horse dewormer!' at you and compare you to Josef Mengele."
it is often possible to make clinical trials come out pretty much any way you want
Marcia Angell, former NEJM editor1026
Hydroxychloroquine. Extensive preclinical research supports efficacy1027-1061. Viruses like SARS-CoV-2 that depend on low pH for endosomal entry1062,1063 can be inhibited with endosomal acidification inhibitors like HCQ(b),1039,1052,1063. Direct clinical measurement shows that HCQ reaches therapeutic concentrations in COVID-19 patients1064, and analysis of lung cells from COVID-19 patients shows inhibition in early target cell types1065,1066.
The largest HCQ/CQ RCT shows 57% lower PCR+ COVID-19 (p=0.0002)(c),534.
Analysis of 424 controlled clinical studies117-543 shows strong evidence for efficacy with early treatment (p<0.0000000001) and prophylaxis (p<0.0000000001), confirmed in multiple additional meta analyses418,1067-1074. The largest HCQ/CQ RCT—the 4,652 patient Oxford/MORU COPCOV RCT—shows 57% lower symptomatic PCR+ COVID-19 with HCQ/CQ (p=0.0002)(c),534. In 2021 Naggie et al.486 showed that HCQ pre-exposure prophylaxis significantly reduces COVID-19 cases based on 2 US RCTs. This is now known with p=0.00004 from RCTs and p=0.00000001 for observational studies.
HCQ shows poor results with late treatment and excessive dosage, and the combination shows harm. Late-stage treatment may enhance viral egress via lysosomal deacidification(d),1075,1076. Research also suggests potential cardioprotective effects at lower doses, but cardiotoxicity with excessive dosage1043. Bobrowski et al. show that HCQ and remdesivir should not be used together. The RECOVERY trial, key to the worldwide campaign against HCQ, used very late treatment with an excessive toxic dose181. Strong evidence for harm from the dose used was confirmed with a dose comparison RCT on April 241078. It is unclear how the trial, with reported IDMC interim reviews every two weeks, could justify starting and continuing this dose until June 5.
HCQ studies (90%) focused on late treatment. Early/preventive trials show selective reporting—failing to report results at a 3x higher rate, suggesting suppression of positive results.
Studies for HCQ are inconsistent with the logical use of antivirals. 90% of treatment studies analyzed late treatment, 5+ days after the onset of symptoms544. This makes it easy to generate meta analyses showing poor efficacy by including large late treatment studies1079, although the results are not relevant to recommended usage. Results have not been reported for 37 RCTs1080-1116, and an additional 65 HCQ RCTs were terminated with <30 patients1117-1175.
HCQ was the first treatment confirmed effective1176, however alternatives may offer advantages. Lung pharmacokinetics show high inter-individual variability1064; dosage is relatively challenging, with dependence on cholesterol1046, lung pH1037, and renal impairment1037, delayed attainment of therapeutic concentrations, and a relatively narrow range of regimens showing efficacy while limiting side effects; and ~2.5%1177 of patients may have contraindications. Longer-term use of endosomal acidification modifiers for prophylaxis raises concern for potential off-target effects, including disruption of cellular processes, impaired lysosomal function, reduced immune response1178, and altered cellular signaling. Fake tablets are common in some locations1179,1180.
There is a clear signal that IVM works in COVID patients..
Ed Mills, Together Trial co-principal investigator1181
Ivermectin. Analysis of 105 clinical studies11-115 shows strong evidence for efficacy (p<0.0000000001), confirmed in multiple additional meta analyses1182-1188. Ivermectin shows efficacy in RCTs for prophylaxis, early treatment, and late treatment. The major RCTs claiming no benefit actually show positive results, despite extreme bias1189.
The largest ivermectin RCT shows faster recovery with probability >0.999 and 36% lower long COVID, p<0.0001, despite extreme bias and very suboptimal design96.
The largest trial, with a design highly favoring finding no efficacy, found superiority with probability > 0.999 for recovery96. Improved recovery is strongly associated with lower mortality, p<0.0000000000196. The trial also found 36% lower long COVID (p<0.0001) despite very suboptimal use96.
A post-exposure prophylaxis RCT showed 96% lower cases with high viral load with ivermectin115. A long COVID RCT showed 4x faster resolution of anosmia89.
Extensive preclinical research supports efficacy(e),1190,1192-1194,1199,1201-1227,1229-1280. Ivermectin also has the most carefully analyzed evidence base in history, resulting in the retraction of a few studies which has improved the quality of the evidence base, and improved the dose-response and treatment delay-response relationships. However the analysis team focused only on issues with positive results1281, showing strong bias1282,1283 and disregarding all flaws and fraud in the major trials claiming no effect116. For example, the main author claims the Together Trial was "incredibly well-done" and a "masterpiece of science" despite the trial reporting multiple impossible numbers, blinding being broken with external sharing during the trial, randomization failure, refusal to share data despite pledging to, no response from the authors, and many protocol violations36.
Optimal use of ivermectin may involve synergy with combined treatments, administration taking into account the lipophilic nature, and sublingual, spray, or inhaled formulations for direct treatment to the respiratory tract. Pharmacokinetics show significant inter-individual variability1284. Injectable formulations may reduce variability and provide much faster onset of action1269. Liposomal formulations show increased antiviral activity and lower cytotoxicity1264. Synergistic results are seen with polytherapy1261,1263,1268. Efficacy varies depending on the manufacturer1285, underdosed and contaminated ivermectin is common1286-1289, and fake tablets with no active ingredient have been reported1290.
Metformin. 106 metformin clinical studies415,421,545-648 show efficacy, confirmed in multiple additional meta analyses1291-1312. Efficacy has also been shown for influenza A1313. Extensive preclinical research supports efficacy(f),552,629,1234,1314-1327.
Antiandrogens. 49 antiandrogen clinical studies650-698 show efficacy, confirmed in multiple additional meta analyses1328,1329. Preclinical research supports efficacy1330-1333. Potential mechanisms include inhibition of TMPRSS2 expression, reduction of androgen-mediated viral entry, modulation of the immune response, and attenuation of inflammation.
Antihistamine H1RAs. 17 antihistamine H1RA clinical studies700-716 show efficacy. Extensive preclinical research supports efficacy702,710,1334-1341.
Curcumin. 28 curcumin clinical studies748-775 show efficacy, confirmed in multiple additional meta analyses1342-1345. Extensive preclinical research supports efficacy(r),1028,1040,1232,1234,1259,1346-1387. Curcumin has low bioavailability and stability1388—COVID-19 efficacy may depend heavily on advanced formulations1389 for improved bioavailability.
Melatonin. 20 melatonin clinical studies777-796 show efficacy, confirmed in multiple additional meta analyses1390-1396. Extensive preclinical research supports efficacy(s),1397-1404. Potential mechanisms include antioxidant, anti-inflammatory, and antithrombotic effects, immune modulation, regulation of autophagy, modulation of the renin-angiotensin system, promotion of sleep and circadian rhythm, and mitigation of cytokine storm.
Colchicine. 57 colchicine clinical studies415,798-853 show efficacy, confirmed in multiple additional meta analyses1405-1414. Preclinical research supports efficacy1374. Potential mechanisms include direct antiviral activity, immunomodulatory and anti-inflammatory effects, cardioprotective effects, and prevention of microvascular thrombosis. Results are poor with very late treatment816—risks due to side effects may exceed benefits.
Probiotics. 28 probiotics clinical studies855-882 show efficacy, confirmed in multiple additional meta analyses1415,1416. Studies also show efficacy for respiratory tract infections1417 and the common cold1418. Preclinical research supports efficacy1419.
NAC. 24 N-acetylcysteine clinical studies922-945 show efficacy, confirmed in multiple additional meta analyses1420,1421. Efficacy has also been shown for influenza1422. Extensive preclinical research supports efficacy(t),1234,1374,1400,1423-1430.
Fluvoxamine. 21 fluvoxamine clinical studies947-967 show efficacy, confirmed in multiple additional meta analyses1431-1439. Preclinical research supports efficacy(u),1440-1443. Potential mechanisms include ASM inhibition, σ-1 receptor activation, antiplatelet effects, endolysosomal interference, HO-1 increase, reduced cytokine storm, and elevated melatonin.
Azvudine. 37 azvudine clinical studies884-920 show efficacy, confirmed in multiple additional meta analyses1444-1447. Preclinical research supports efficacy1448.
Nigella Sativa. 14 nigella sativa clinical studies969-982 show efficacy, confirmed in multiple additional meta analyses1449,1450. Extensive preclinical research supports efficacy1028,1451-1468. Potential mechanisms include direct antiviral activity, and immunomodulatory, antioxidant, and anti-inflammatory action.
Famotidine. 30 famotidine clinical studies410,415,984-1010 show efficacy. Preclinical research supports efficacy1469. Potential mechanisms include direct antiviral activity, anti-inflammatory effects and reduced cytokine release, reduced acidity altering conditions for viral replication, immune modulation, and anticoagulant effects.
TMPRSS2 inhibitors. 29 TMPRSS2 inhibitor clinical studies718-746 show efficacy. Extensive preclinical research supports efficacy1027,1232,1237,1470-1477.
Quercetin. 12 quercetin clinical studies1012-1023 show efficacy, confirmed in multiple additional meta analyses1478,1479. Extensive preclinical research supports efficacy(ap),1028,1030,1232,1347,1351,1355,1359,1362,1363,1371,1376,1480,1482-1537. Potential mechanisms include direct antiviral activity, antioxidant and anti-inflammatory activity, and immune support. COVID-19 efficacy may depend heavily on advanced formulations for improved bioavailability.
Protocols typically combine multiple treatments. No single treatment is guaranteed to be effective and safe for a specific individual. Leading evidence-based protocols combine multiple treatments.
c19early.org
Combined treatments increase efficacy
Monotherapy33% [30‑36%]
Polytherapy68% [57‑77%]
Meta analysis of early treatment studies.
Complementary and synergistic actions. There are many complementary mechanisms of action across treatments, and studies show complementary and synergistic effects with polytherapy81,1056,1261,1263,1268,1271,1474,1475,1538-1546. For example, Jitobaom et al.1263 shows >10x reduction in IC50 with ivermectin and niclosamide, an RCT by Said et al.1541 showed the combination of nigella sativa and vitamin D was more effective than either alone, and an RCT by Wannigama et al.958 showed improved results with fluvoxamine combined with additional treatments, compared to fluvoxamine alone. Treatment efficacy may vary significantly across SARS-CoV-2 variants. For example new variants may gain resistance to targeted treatments1547-1553, and the role of TMPRSS2 for cell entry differs across variants1554. The efficacy of specific treatments varies depending on cell type1555 due to differences in viral receptor expression, drug distribution and metabolism, cell-specific mechanisms, and the relevance of drug targets to specific cells. Efficacy may also vary based on genetic variants1556-1561. Variable efficacy across SARS-CoV-2 variants, cell types, different tissues, and host genetics, along with the complementary and synergistic actions of different treatments, all point to greater efficacy with polytherapy. In many studies, the standard of care given to all patients includes other treatments—efficacy seen in these trials may rely in part on synergistic effects. Meta analysis of all early treatment trials shows 68% [57‑77%] lower risk for studies using combined treatments, compared to 33% [30‑36%] for single treatments.
SARS-CoV-2 evolution and the risk of escape mutants suggests treatments with broader mechanisms of action and polytherapy. SARS-CoV-2 can rapidly acquire mutations altering infectivity, disease severity, and drug resistance even without selective pressure1562. Antigenic drift can undermine more variant-specific treatments like monoclonal antibodies and more specific antivirals. Treatment with targeted antivirals may select for escape mutations1563. Less variant specific treatments and polytherapy targeting multiple viral and host proteins may be more effective.
Systemic antivirals may be less applicable to low-risk infections. As SARS-CoV-2 has evolved, the frequency of serious infections has reduced. Systemic antivirals may have a more limited effect if infection does not spread beyond the upper respiratory tract.
Defined as ≥3 studies showing ≥10% improvement or >0% harm with statistical significance in meta analysis.
The efficacy of endosomal entry inhibitors varies across SARS-CoV-2 variants, depending on their reliance on the endosomal pathway for entry. SARS-CoV-2 uses two major pathways for host cell entry: endosomal entry via cathepsin proteases and TMPRSS2-mediated plasma membrane fusion. Studies show increased reliance on TMPRSS2-mediated entry for the Delta variant compared to the original strain. Conversely, Omicron variants have shown significantly greater reliance on endosomal entry, suggesting increased efficacy of endosomal acidification inhibitors. Specific sub-variants may vary. A dual-inhibition strategy targeting both pathways may be preferred.
COPCOV has the largest number of treated patients of all HCQ/CQ RCTs.
When administered late in infection, HCQ may enhance viral egress by further increasing lysosomal pH beyond the effect of ORF3a's water channel activity, thereby promoting lysosomal exocytosis, inactivating degradative enzymes, and facilitating the release of SARS-CoV-2 particles into the extracellular environment1075,1076.
Ivermectin, better known for antiparasitic activity, is a broad spectrum antiviral with activity against many viruses including H7N71190, Dengue1191-1193, HIV-11192, Simian virus 401194, Zika1193,1195,1196, West Nile1196, Yellow Fever1197,1198, Japanese encephalitis1197, Chikungunya1198, Semliki Forest virus1198, Human papillomavirus1199, Epstein-Barr1199, BK Polyomavirus1200, and Sindbis virus1198. Ivermectin inhibits importin-α/β-dependent nuclear import of viral proteins1190,1192,1194,1201, shows spike-ACE2 disruption at 1nM with microfluidic diffusional sizing1202, binds to glycan sites on the SARS-CoV-2 spike protein preventing interaction with blood and epithelial cells and inhibiting hemagglutination1203,1204, shows dose-dependent inhibition of wildtype and omicron variants1205, exhibits dose-dependent inhibition of lung injury1206,1207, may inhibit SARS-CoV-2 via IMPase inhibition1193, may inhibit SARS-CoV-2 induced formation of fibrin clots resistant to degradation1208, inhibits SARS-CoV-2 3CLpro1209, may inhibit SARS-CoV-2 RdRp activity1210, may minimize viral myocarditis by inhibiting NF-κB/p65-mediated inflammation in macrophages1211, may be beneficial for COVID-19 ARDS by blocking GSDMD and NET formation1212, may interfere with SARS-CoV-2's immune evasion via ORF8 binding1213, may inhibit SARS-CoV-2 by disrupting CD147 interaction1214-1217, shows protection against inflammation, cytokine storm, and mortality in an LPS mouse model sharing key pathological features of severe COVID-191218,1219, may be beneficial in severe COVID-19 by binding IGF1 to inhibit the promotion of inflammation, fibrosis, and cell proliferation that leads to lung damage1220, may minimize SARS-CoV-2 induced cardiac damage1221,1222, may counter immune evasion by inhibiting NSP15-TBK1/KPNA1 interaction and restoring IRF3 activation1223, may disrupt SARS-CoV-2 N and ORF6 protein nuclear transport and their suppression of host interferon responses1224, reduces TAZ/YAP nuclear import, relieving SARS-CoV-2-driven suppression of IRF3 and NF-κB antiviral pathways1225, increases Bifidobacteria which play a key role in the immune system1226, has immunomodulatory1227 and anti-inflammatory1228,1229 properties, and has an extensive and very positive safety profile1230.
A systematic review and meta-analysis of 15 non-COVID-19 preclinical studies showed that metformin inhibits pulmonary inflammation and oxidative stress, minimizes lung injury, and improves survival in animal models of acute respiratory distress syndrome (ARDS) or acute lung injury (ALI)1314. Metformin inhibits SARS-CoV-2 in vitro552,1315, minimizes LPS-induced cytokine storm in a mouse model1316, minimizes lung damage and fibrosis in a mouse model of LPS-induced ARDS629, may protect against SARS-CoV-2-induced neurological disorders1317, may be beneficial via inhibitory effects on ORF3a-mediated inflammasome activation1318, reduces UUO and FAN-induced kidney fibrosis629, increases mitochondrial function and decreases TGF-β-induced fibrosis, apoptosis, and inflammation markers in lung epithelial cells629, may reduce inflammation, oxidative stress, and thrombosis via regulating glucose metabolism1319, attenuates spike protein S1-induced inflammatory response and α-synuclein aggregation1320, may reduce COVID-19 severity and long COVID by inhibiting NETosis via suppression of protein kinase C activation1321, enhances interferon responses and reduces SARS-CoV-2 infection and inflammation in diabetic models by suppressing HIF-1α signaling1322, may improve COVID-19 outcomes by preventing VDAC1 mistargeting to the plasma membrane, reducing ATP loss, and preserving immune cell function during cytokine storm1323, reduces hyperglycemia-induced hepatic ACE2/TMPRSS2 up-regulation and SARS-CoV-2 entry1324, and may improve outcomes via modulation of immune responses with increased anti-inflammatory T lymphocyte gene expression and via enhanced gut microbiota diversity1325.
The trimeric spike (S) protein is a glycoprotein that mediates viral entry by binding to the host ACE2 receptor, is critical for SARS-CoV-2's ability to infect host cells, and is a target of neutralizing antibodies. Inhibition of the spike protein prevents viral attachment, halting infection at the earliest stage.
The receptor binding domain is a specific region of the spike protein that binds ACE2 and is a major target of neutralizing antibodies. Focusing on the precise binding site allows highly specific disruption of viral attachment with reduced potential for off-target effects.
The main protease or Mpro, also known as 3CLpro or nsp5, is a cysteine protease that cleaves viral polyproteins into functional units needed for replication. Inhibiting Mpro disrupts the SARS-CoV-2 lifecycle within the host cell, preventing the creation of new copies.
RNA-dependent RNA polymerase (RdRp), also called nsp12, is the core enzyme of the viral replicase-transcriptase complex that copies the positive-sense viral RNA genome into negative-sense templates for progeny RNA synthesis. Inhibiting RdRp blocks viral genome replication and transcription.
The papain-like protease (PLpro) has multiple functions including cleaving viral polyproteins and suppressing the host immune response by deubiquitination and deISGylation of host proteins. Inhibiting PLpro may block viral replication and help restore normal immune responses.
The angiotensin converting enzyme 2 (ACE2) protein is a host cell transmembrane protein that serves as the cellular receptor for the SARS-CoV-2 spike protein. ACE2 is expressed on many cell types, including epithelial cells in the lungs, and allows the virus to enter and infect host cells. Inhibition may affect ACE2's physiological function in blood pressure control.
The nucleocapsid (N) protein binds and encapsulates the viral genome by coating the viral RNA. N enables formation and release of infectious virions and plays additional roles in viral replication and pathogenesis. N is also an immunodominant antigen used in diagnostic assays.
Non-structural protein 10 (nsp10) serves as an RNA chaperone and stabilizes conformations of nsp12 and nsp14 in the replicase-transcriptase complex, which synthesizes new viral RNAs. Nsp10 disruption may destabilize replicase-transcriptase complex activity.
The helicase, or nsp13, protein unwinds the double-stranded viral RNA, a crucial step in replication and transcription. Inhibition may prevent viral genome replication and the creation of new virus components.
The interaction between the SARS-CoV-2 spike protein and the human ACE2 receptor is a primary method of viral entry, inhibiting this interaction can prevent the virus from attaching to and entering host cells, halting infection at an early stage.
Transmembrane protease serine 2 (TMPRSS2) is a host cell protease that primes the spike protein, facilitating cellular entry. TMPRSS2 activity helps enable cleavage of the spike protein required for membrane fusion and virus entry. Inhibition may especially protect respiratory epithelial cells, buy may have physiological effects.
In Silico studies predict inhibition of SARS-CoV-2 with curcumin or metabolites via binding to the spike(g),1232,1346-1351 (and specifically the receptor binding domain(h),1352-1355), Mpro(i),1232,1347,1348,1350,1351,1353-1363, RNA-dependent RNA polymerase(j),1232,1351,1354,1355,1364, PLpro(k),1232, ACE2(l),1028,1349,1362, nucleocapsid(m),1259,1365, nsp10(n),1259, and helicase(o),1366 proteins, and inhibition of spike-ACE2 interaction(p),1367. In Vitro studies demonstrate inhibition of the spike(g),1040 (and specifically the receptor binding domain(h),1368), Mpro(i),1040,1363,1369,1370, ACE2(l),1368, and TMPRSS2(q),1368 proteins, and inhibition of spike-ACE2 interaction(p),1367,1371. Curcumin is predicted to inhibit the interaction between the SARS-CoV-2 spike protein receptor binding domain and the human ACE2 receptor for the delta and omicron variants1352, decreases pro-inflammatory cytokines induced by SARS-CoV-2 in peripheral blood mononuclear cells1372, alleviates SARS-CoV-2 spike protein-induced mitochondrial membrane damage and oxidative stress1373, may limit COVID-19 induced cardiac damage by inhibiting the NF-κB signaling pathway which mediates the profibrotic effects of the SARS-CoV-2 spike protein on cardiac fibroblasts1374, lowers ACE2 and STAT3, curbing lung inflammation and ARDS in preclinical COVID-19 models1375, and inhibits SARS-CoV-2 ORF3a ion channel activity, which contributes to viral pathogenicity and cytotoxicity1376.
Melatonin may restore altered redox homeostasis in COVID-191397, modulates type III interferon responses and reduces inflammatory cytokine production in TLR3 receptor agonist stimulated viral inflammation while preserving tissue integrity1398, and negatively regulates genes critical for viral entry in lung tissue, including reduced expression of FURIN and components of the CD147 complex, while potentially disrupting TMPRSS2/ACE2-mediated entry mechanisms1399. Melatonin reduces oxidative stress, inhibits NET formation, and protects tissues through anti-inflammatory and antioxidant actions1400.
N-acetylcysteine shows dose-dependent inhibition of SARS-CoV-21423-1425, shows anti-inflammatory and immunomodulatory effects against SARS-CoV-2-induced immune responses in combination with bromelain1426, suppressed virus-induced reactive oxygen species and blocked viral replication in a humanized mouse model and in human lung cells1427, may limit COVID-19 induced cardiac damage by boosting cellular antioxidant defenses and potentially mitigating the oxidative stress caused by spike protein-induced ROS production in cardiac fibroblasts1374, and reduces disulfide bonds in proteins and exhibits antioxidant properties that may inhibit viral replication and modulate inflammatory responses1428. NAC may be beneficial for COVID-19 by replenishing glutathione stores and reinforcing the glutathione peroxidase-4 pathway to inhibit ferroptosis, an oxidative stress-induced cell death pathway implicated in COVID-191429. NAC reinforces glutathione levels, reduces ROS, and minimizes ferroptosis and cytokine storm1400.
Fluvoxamine may inhibit SARS-CoV-2 cell entry by preventing the formation of ceramide platforms that facilitates viral uptake1440, may help restore autophagic processes disrupted by NSP6, thereby reducing SARS-CoV-2 replication and improving host cellular defenses1441, and may reduce COVID-19 thrombotic complications by inhibiting serotonin reuptake and decreasing platelet activation1442.
The endoribonuclease, also known as NendoU or nsp15, cleaves specific sequences in viral RNA which may help the virus evade detection by the host immune system. Inhibition may hinder the virus's ability to mask itself from the immune system, facilitating a stronger immune response.
The NSP16/10 complex consists of non-structural proteins 16 and 10, forming a 2'-O-methyltransferase that modifies the viral RNA cap structure. This modification helps the virus evade host immune detection by mimicking host mRNA, making NSP16/10 a promising antiviral target.
Cathepsin L is a host lysosomal cysteine protease that can prime the spike protein through an alternative pathway when TMPRSS2 is unavailable. Dual targeting of cathepsin L and TMPRSS2 may maximize disruption of alternative pathways for virus entry.
Wingless-related integration site (Wnt) ligand 3 is a host signaling molecule that activates the Wnt signaling pathway, which is important in development, cell growth, and tissue repair. Some studies suggest that SARS-CoV-2 infection may interfere with the Wnt signaling pathway, and that Wnt3a is involved in SARS-CoV-2 entry.
The frizzled (FZD) receptor is a host transmembrane receptor that binds Wnt ligands, initiating the Wnt signaling cascade. FZD serves as a co-receptor, along with ACE2, in some proposed mechanisms of SARS-CoV-2 infection. The virus may take advantage of this pathway as an alternative entry route.
Low-density lipoprotein receptor-related protein 6 is a cell surface co-receptor essential for Wnt signaling. LRP6 acts in tandem with FZD for signal transduction and has been discussed as a potential co-receptor for SARS-CoV-2 entry.
The ezrin protein links the cell membrane to the cytoskeleton (the cell's internal support structure) and plays a role in cell shape, movement, adhesion, and signaling. Drugs that occupy the same spot on ezrin where the viral spike protein would bind may hindering viral attachment, and drug binding could further stabilize ezrin, strengthening its potential natural capacity to impede viral fusion and entry.
The Adipocyte Differentiation-Related Protein (ADRP, also known as Perilipin 2 or PLIN2) is a lipid droplet protein regulating the storage and breakdown of fats in cells. SARS-CoV-2 may hijack the lipid handling machinery of host cells and ADRP may play a role in this process. Disrupting ADRP's interaction with the virus may hinder the virus's ability to use lipids for replication and assembly.
Neuropilin-1 (NRP1) is a cell surface receptor with roles in blood vessel development, nerve cell guidance, and immune responses. NRP1 may function as a co-receptor for SARS-CoV-2, facilitating viral entry into cells. Blocking NRP1 may disrupt an alternative route of viral entry.
EP300 (E1A Binding Protein P300) is a transcriptional coactivator involved in several cellular processes, including growth, differentiation, and apoptosis, through its acetyltransferase activity that modifies histones and non-histone proteins. EP300 facilitates viral entry into cells and upregulates inflammatory cytokine production.
Prostaglandin G/H synthase 2 (PTGS2, also known as COX-2) is an enzyme crucial for the production of inflammatory molecules called prostaglandins. PTGS2 plays a role in the inflammatory response that can become severe in COVID-19 and inhibitors (like some NSAIDs) may have benefits in dampening harmful inflammation, but note that prostaglandins have diverse physiological functions.
Heat Shock Protein 90 Alpha Family Class A Member 1 (HSP90AA1) is a chaperone protein that helps other proteins fold correctly and maintains their stability. HSP90AA1 plays roles in cell signaling, survival, and immune responses. HSP90AA1 may interact with numerous viral proteins, but note that it has diverse physiological functions.
Matrix metalloproteinase 9 (MMP9), also called gelatinase B, is a zinc-dependent enzyme that breaks down collagen and other components of the extracellular matrix. MMP9 levels increase in severe COVID-19. Overactive MMP9 can damage lung tissue and worsen inflammation. Inhibition of MMP9 may prevent excessive tissue damage and help regulate the inflammatory response.
The interleukin-6 (IL-6) pro-inflammatory cytokine (signaling molecule) has a complex role in the immune response and may trigger and perpetuate inflammation. Elevated IL-6 levels are associated with severe COVID-19 cases and cytokine storm. Anti-IL-6 therapies may be beneficial in reducing excessive inflammation in severe COVID-19 cases.
The interleukin-10 (IL-10) anti-inflammatory cytokine helps regulate and dampen immune responses, preventing excessive inflammation. IL-10 levels can also be elevated in severe COVID-19. IL-10 could either help control harmful inflammation or potentially contribute to immune suppression.
Vascular Endothelial Growth Factor A (VEGFA) promotes the growth of new blood vessels (angiogenesis) and has roles in inflammation and immune responses. VEGFA may contribute to blood vessel leakiness and excessive inflammation associated with severe COVID-19.
RELA is a transcription factor subunit of NF-kB and is a key regulator of inflammation, driving pro-inflammatory gene expression. SARS-CoV-2 may hijack and modulate NF-kB pathways.
A mouse model expressing the human ACE2 receptor under the control of the K18 promoter.
A mouse model of obesity and severe insulin resistance leading to type 2 diabetes due to a mutation in the leptin receptor gene that impairs satiety signaling.
A mouse model commonly used in infectious disease and cancer research due to higher immune response and susceptibility to infection.
In Silico studies predict inhibition of SARS-CoV-2, or minimization of side effects, with quercetin or metabolites via binding to the spike(g),1030,1232,1347,1351,1362,1480-1488 (and specifically the receptor binding domain(h),1355), Mpro(i),1030,1232,1347,1351,1355,1359,1362,1483,1484,1486,1489-1503, RNA-dependent RNA polymerase(j),1232,1351,1355,1486,1504,1505, PLpro(k),1232,1491,1496, ACE2(l),1028,1362,1482,1487,1491,1492, TMPRSS2(q),1482, nucleocapsid(m),1232, helicase(o),1232,1490,1506, endoribonuclease(v),1480, NSP16/10(w),1507, cathepsin L(x),1508, Wnt-3(y),1482, FZD(z),1482, LRP6(aa),1482, ezrin(ab),1509, ADRP(ac),1030, NRP1(ad),1487, EP300(ae),1510, PTGS2(af),1492, HSP90AA1(ag),1492,1510, matrix metalloproteinase 9(ah),1511, IL-6(ai),1512,1513, IL-10(aj),1512, VEGFA(ak),1513, and RELA(al),1513 proteins, and inhibition of spike-ACE2 interaction(p),1514. In Vitro studies demonstrate inhibition of the Mpro(i),1363,1498,1515,1516 protein, and inhibition of spike-ACE2 interaction(p),1371. Animal studies demonstrate efficacy in K18-hACE2 mice(am),1517, db/db mice(an),1518,1519, BALB/c mice(ao),1520, and rats1521. Quercetin reduced proinflammatory cytokines and protected lung and kidney tissue against LPS-induced damage in mice1520, inhibits LPS-induced cytokine storm by modulating key inflammatory and antioxidant pathways in macrophages1522, may block ACE2-spike interaction and NLRP3 inflammasome, limiting viral entry and inflammation1523, and inhibits SARS-CoV-2 ORF3a ion channel activity, which contributes to viral pathogenicity and cytotoxicity1376.
Please send us corrections, updates, or comments. c19early involves the extraction of 200,000+ datapoints from thousands of papers. Community updates help ensure high accuracy. Treatments and other interventions are complementary. All practical, effective, and safe means should be used based on risk/benefit analysis. No treatment or intervention is 100% available and effective for all current and future variants. We do not provide medical advice. Before taking any medication, consult a qualified physician who can provide personalized advice and details of risks and benefits based on your medical history and situation. IMA and WCH provide treatment protocols.
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