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Iota-carrageenan for COVID-19
1 study from 18 scientists
394 patients in 1 country
Statistically significant lower risk for cases.
COVID-19 Iota-carrageenan studies. Apr 2024.
0 0.5 1 1.5+ All studies 80% Cases 80% RCTs 80% Prophylaxis 80% Favorscarrageenan Favorscontrol
Apr 17
Covid Analysis Iota-carrageenan for COVID-19: real-time meta analysis of 1 study
Statistically significant lower risk is seen for cases. Meta analysis using the most serious outcome reported shows 80% [22‑95%] lower risk. Currently there is very limited data, with only one study to date. 1 RCT with 480 pati..
Mar 28
Yathindranath et al., International Journal of Nanomedicine, doi:10.2147/IJN.S448005 Lipid Nanoparticle-Based Inhibitors for SARS-CoV-2 Host Cell Infection
In Vitro study showing that lactoferrin, camostat mesylate, and carrageenan inhibit SARS-CoV-2 pseudovirus infection in airway epithelial Calu-3 cells. All show dose-dependent inhibition. The study focuses on novel LNP formulations and t..
Jul 31
Rohilla et al., Stresses, doi:10.3390/stresses3030039 Algae Polysaccharides (Carrageenan and Alginate)—A Treasure-Trove of Antiviral Compounds: An In Silico Approach to Identify Potential Candidates for Inhibition of S1-RBD Spike Protein of SARS-CoV-2
In silico study showing the potential antiviral activity of algal polysaccharides alginate and carrageenan against SARS-CoV-2. Molecular docking analyses predict that alginate and carrageenan can bind to and inhibit the viral S1-RBD spike..
Jul 5
Setz et al., Nutraceuticals, doi:10.3390/nutraceuticals3030025 Iota-Carrageenan Inhibits Replication of the SARS-CoV-2 Variants of Concern Omicron BA.1, BA.2 and BA.5
In Vitro study showing that iota-carrageenan inhibits SARS-CoV-2 replication for omicron variants BA.1, BA.2 and BA.5. Iota-carrageenan was more effective than kappa- and lambda-carrageenan.
Feb 27
Chavda et al., Pharmacological Reports, doi:10.1007/s43440-023-00463-7 Nasal sprays for treating COVID-19: a scientific note
Review of nasal sprays for treatment of COVID-19. Authors note that the nasal epithelium is typically the primary site of SARS-CoV-2 infection, and there may be significant advantages for treatments via the nasal route.
Nov 22
Thet, H., Journal of Bioinformatics and Genomics, doi:10.18454/jbg.2022.18.2.001 The potential of carrageenan for the drug discovery of COVID-19 via molecular docking with angiotensin-converting enzyme 2 (ACE2) and the main protease (Mpro) of SARS-CoV-2
In SIlico study identifying significant binding affinity for ACE2 and Mpro with kappa-, lambda-, and iota-carrageenan.
Nov 18
Jessop et al., NCT04590365 Efficacy of Carrageenan Nasal and Throat Spray for COVID-19 Prophylaxis - A Double Blind Randomised Placebo-controlled Trial
480 participant iota-carrageenan prophylaxis RCT with results not reported over 1 year after completion.
Sep 30
Kreutzberger et al., Proceedings of the National Academy of Sciences, doi:10.1073/pnas.2209514119 SARS-CoV-2 requires acidic pH to infect cells
Real-time 3D single-virion tracking study showing that SARS-CoV-2 infection requires an acidic pH. Authors find the mean pH of the airway-facing surface of the nasal cavity to be 6.6, compatible with fusion. These results suggest a benefi..
Feb 28
Meister et al., Journal of Hospital Infection, doi:10.1016/j.jhin.2021.10.019 Virucidal activity of nasal sprays against severe acute respiratory syndrome coronavirus-2
In Vitro study of seven nasal sprays and two oral sprays showing 3.4x lower viral load (log viral load 5.98->5.45) with a nasal spray containing carragelose (1.2 mg/mL), kappa-carrageenan (0.4 mg/mL), and sodium chlorite. The most effecti..
Dec 15
Bovard et al., Biochemistry and Biophysics Reports, doi:10.1016/j.bbrep.2021.101187 Iota-carrageenan extracted from red algae is a potent inhibitor of SARS-CoV-2 infection in reconstituted human airway epithelia
In Vitro study showing iota-carrageenan inhibits SARS-CoV-2 in reconstituted human airway epithelia. Authors note that the absence of toxicity or any functional or structural impairment of the bronchial mucociliary epithelium indicates th..
Dec 8
Fröba et al., International Journal of Molecular Sciences, doi:10.3390/ijms222413202 Iota-Carrageenan Inhibits Replication of SARS-CoV-2 and the Respective Variants of Concern Alpha, Beta, Gamma and Delta
In Vitro study of iota-, lambda-, and kappa-carrageenan sulfated polysaccharides extracted from red seaweed on SARS-CoV-2 Wuhan type and variants Alpha, Beta, Gamma and Delta, showing that all three carrageenan types had antiviral activit..
Sep 7
Morokutti-Kurz et al., International Journal of General Medicine, doi:10.2147/IJGM.S325861 The Saliva of Probands Sucking an Iota-Carrageenan Containing Lozenge Inhibits Viral Binding and Replication of the Most Predominant Common Cold Viruses and SARS-CoV-2
Prospective study of 31 subjects analyzing iota-carrageenan concentration in saliva after using an iota-carrageenan containing lozenge, showing sufficient concentration to neutralize common respiratory viruses including SARS-CoV-2. For SA..
Aug 30
Niculescu et al., NCT04681001 Clinical Trial to Evaluate the Efficacy of an Iota-Carrageenan Nasal Spray to Reduce Symptoms Caused by SARS-CoV-2 and Other Respiratory Viruses in Healthcare Workers Managing COVID-19 Patients
300 participant iota-carrageenan prophylaxis RCT with results not reported over 2 years after completion. Authors indicate that there were no SARS-CoV-2 infections in either group. The trial record also suggests there was no placebo group..
Jul 26
Alsaidi et al., Marine Drugs, doi:10.3390/md19080418 Griffithsin and Carrageenan Combination Results in Antiviral Synergy against SARS-CoV-1 and 2 in a Pseudoviral Model
In Vitro and In Silico analysis showing SARS-CoV-2 antiviral activity of carageenan, and synergistic activity from the combination of carrageenan and griffithsin.
Jun 16
Robinson et al., Frontiers in Medical Technology, doi:10.3389/fmedt.2021.687681 Low Acyl Gellan as an Excipient to Improve the Sprayability and Mucoadhesion of Iota Carrageenan in a Nasal Spray to Prevent Infection With SARS-CoV-2
Formulation of a carrageenan nasal spray using gellan as an excipient to improve sprayability and mucoadhesion. Authors report 4x greater coverage versus carrageenan alone. See also [Moakes].
Jun 14
Hemilä et al., Pharmacology Research and Perspectives, doi:10.1002/prp2.810 Carrageenan nasal spray may double the rate of recovery from coronavirus and influenza virus infections: Re-analysis of randomized trial data
Individual patient data meta analysis of two RCTs showing nasal iota-carrageenan improved recovery rate and shortened the duration of long colds. There was a 71% reduction in the risk of long colds (>20 days). The increase in recovery rat..
May 31
Moakes et al., Advanced Materials, doi:10.1002/adma.202008304 Formulation of a Composite Nasal Spray Enabling Enhanced Surface Coverage and Prophylaxis of SARS‐COV‐2
Formulation of a mucoadhesive antiviral nasal spray showing efficacy for prophylaxis and against transmission. In Vitro analysis shows prophylaxis with λ-carrageenan demonstrated complete inhibition of SARS-CoV-2 over 48h. A combination o..
Apr 28
Schütz et al., American Journal of Physiology: Lung Cellular and Molecular Physiology, doi:10.1152/ajplung.00552.2020 Carrageenan-containing over-the-counter nasal and oral sprays inhibit SARS-CoV-2 infection of airway epithelial cultures
In Vitro study showing that carrageenan-containing nose spray and mouth spray inhibit SARS-CoV-2 in human airway epithelial cultures.
Apr 27
Varese et al., bioRxiv, doi:10.1101/2021.04.27.441512 Iota-carrageenan prevents the replication of SARS-CoV-2 on an in vitro respiratory epithelium model
In Vitro Calu-3 (human respiratory epithelial cell line) study showing that iota-carrageenan inhibits SARS-CoV-2.
Apr 15
Figueroa et al., International Journal of General Medicine, doi:10.2147/IJGM.S328486 (date from preprint) Efficacy of a nasal spray containing Iota-Carrageenan in the prophylaxis of COVID-19 in hospital personnel dedicated to patients care with COVID-19 disease A pragmatic multicenter, randomized, double-blind, placebo-controlled trial (CARR-COV-02)
80% fewer symptomatic cases (p=0.03). Prophylaxis RCT with 394 healthcare workers, 196 treated with iota-carrageenan, showing significantly lower symptomatic cases with treatment. There were no deaths or hospitalizations. There was a significant number of PCR- symptomatic cas..
Feb 17
Morokutti-Kurz et al., PLoS ONE, doi:10.1371/journal.pone.0237480 Iota-carrageenan neutralizes SARS-CoV-2 and inhibits viral replication in vitro
In Vitro study showing that SARS-CoV-2 is inhibited by iota-carrageenan in a dose dependent manner and to the same extent as other respiratory viruses for which a clinical benefit has been proven. Authors note that clinical data and post ..
Jan 11
Chahla et al., American Journal of Therapeutics, doi:10.1097/MJT.0000000000001433 Intensive Treatment With Ivermectin and Iota-Carrageenan as Pre-exposure Prophylaxis for COVID-19 in Health Care Workers From Tucuman, Argentina
95% fewer moderate/severe cases (p=0.002) and 84% fewer cases (p=0.004). Prophylaxis RCT for ivermectin and iota-carrageenan in Argentina, 117 healthcare workers treated with ivermectin and iota-carrageenan, and 117 controls, showing significantly lower cases with treatment. There were no moderate/severe cases..
Dec 29
Hans et al., Bioresource Technology Reports, doi:10.1016/j.biteb.2020.100623 Antiviral activity of sulfated polysaccharides from marine algae and its application in combating COVID-19: Mini review
Review of the antiviral activity of marine sulfated polysaccharides including carrageenan, and the mechanisms of action for inhibiting different stages of viral infection.
Nov 17
Carvallo et al., Journal of Biomedical Research and Clinical Investigation, doi:10.31546/2633-8653.1007 Study of the Efficacy and Safety of Topical Ivermectin + Iota-Carrageenan in the Prophylaxis against COVID-19 in Health Personnel
100% fewer cases (p<0.0001). Prophylaxis study using ivermectin and iota-carrageenan showing 0 of 788 cases from treated healthcare workers, compared to 237 of 407 control. See [] for discussion of issues with this trial.
Aug 24
Song et al., Food & Function, doi:10.1039/D0FO02017F Inhibitory activities of marine sulfated polysaccharides against SARS-CoV-2
In Vitro study showing significant antiviral activity of marine sulfated polysaccharides iota-carrageenan, sea cucumber sulfated polysaccharide, and fucoidan.
Aug 21
Bansal et al., PLoS ONE, doi:10.1371/journal.pone.0259943 (date from preprint) Iota-carrageenan and xylitol inhibit SARS-CoV-2 in Vero cell culture
In Vitro study showing that iota-carrageenan in concentrations as low as 6 µg/mL (easily achievable with existing nasal sprays) inhibits SARS-CoV-2 in Vero cell cultures.
Jun 29
Sattari et al., Research Square, doi:10.21203/ Repositioning Therapeutics for COVID-19: Virtual Screening of the Potent Synthetic and Natural Compounds as SARS-CoV-2 3CLpro Inhibitors
In Silico study identifying kappa-carrageenan and other compounds as potential candidates for SARS-CoV-2 inhibition.
Feb 28
Morokutti-Kurz et al., International Journal of General Medicine, doi:10.2147/IJGM.S120665 Amylmetacresol/2,4-dichlorobenzyl alcohol, hexylresorcinol, or carrageenan lozenges as active treatments for sore throat
Pre-COVID In Vitro study showing iota-carrageenan lozenges effective against respiratory viruses HRV1a, HRV8, Coxsackievirus A10, influenza A H1N1n, and hCoV OC43.
Nov 12
Koenighofer et al., Multidisciplinary Respiratory Medicine, doi:10.1186/2049-6958-9-57 Carrageenan nasal spray in virus confirmed common cold: individual patient data analysis of two randomized controlled trials
Analysis of 2 RCTs concluding that carrageenan nasal spray reduced duration of virus-confirmed common colds, increased viral clearance, and reduced relapses.
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