Efficacy of a Nasal Spray Containing Iota-Carrageenan in the Postexposure Prophylaxis of COVID-19 in Hospital Personnel Dedicated to Patients Care with COVID-19 Disease

Abstract

Background Iota-Carrageenan (I-C) is a sulfate polysaccharide synthesized by red algae, with demonstrated antiviral activity and clinical efficacy as nasal spray in the treatment of common cold. In vitro, I-C inhibits SARS-CoV-2 infection in cell culture. Research Question Can a nasal spray with Iota-Carrageenan be useful in the prophylaxis of COVID-19 in health care workers managing patients with COVID-19 disease? Study Design and Methods This is a pilot pragmatic multicenter, randomized, double-blind, placebo-controlled study assessing the use of a nasal spray containing I-C in the prophylaxis of COVID-19 in hospital personnel dedicated to care of COVID-19 patients. Clinically healthy physicians, nurses, kinesiologists and other health care providers managing patients hospitalized for COVID-19 were assigned in a 1:1 ratio to receive four daily doses of I-C spray or placebo for 21 days. The primary end point was clinical COVID-19, as confirmed by reverse transcriptase polymerase chain reaction testing, over a period of 21 days. The trial is registered at ClinicalTrials.gov (NCT04521322). Results A total of 394 individuals were randomly assigned to receive I-C or placebo. Both treatment groups had similar baseline characteristics. The incidence of COVID-19 differs significantly between subjects receiving the nasal spray with I-C (2 of 196 [1.0%]) and those receiving placebo (10 of 198 [5.0%]). Relative risk reduction: 79.8% (95% CI 5.3 to 95.4; p=0.03). Absolute risk reduction: 4% (95% CI 0.6 to 7.4). Interpretation In this pilot study a nasal spray with I-C showed significant efficacy in preventing COVID-19 in health care workers managing patients with COVID-19 disease. Clinical Trials Registration NCT04521322.

Iota-carrageenan and xylitol inhibit SARS-CoV-2 in Vero cell culture

“…Randomized, double-blind, placebo-controlled clinical trials are needed to confirm that the in vitro results obtained in our experiments correlate in vivo. A pilot study has been recently published showing a significant reduction in the risk of transmission in healthy hospital personnel dedicated patients when using an iota-carrageenan nasal spray corresponding to the composition of sample 1 of our experiment (1.7 mg/mL iota-carrageenan in 0.9% sodium chloride) in addition to standard preventive measures (ClinicalTrials.gov Identifier: NCT04521322) [42].…”

Iota-Carrageenan Inhibits Replication of SARS-CoV-2 and the Respective Variants of Concern Alpha, Beta, Gamma and Delta

“…Very recently, it was shown in a multicenter, randomized, double-blinded, placebocontrolled clinical study, that an iota-carrageenan containing nasal spray exhibits prophylactic efficacy in preventing SARS-CoV-2 infection in healthcare workers caring for patients with COVID-19 disease with a relative risk reduction of 79.8% [46]. An earlier trial investigating a nasal spray containing Ivermectin and iota-carrageenan showed reduction in COVID-19 as well as of disease severity [47].…”

Iota-Carrageenan Prevents the Replication of SARS-CoV-2 in a Human Respiratory Epithelium Cell Line in vitro

“…If we take an average content of 200 µl of liquid from the surface of the airways in the nose plus 200 µl of the formulation after administering 100 µl of the solution in each nostril, the immediate concentration of iota-carrageenan in the nasal cavity would be 600 µg/ml, the highest concentration tested in our investigation. The expected concentrations of iotacarrageenan in the nasal cavity would be even higher if we consider a nasal formulation containing 1.7 mg/ml, like the one used in the only clinical trial published on the efficacy of a nasal spray with iota-carrageenan in the prevention of COVID-19, research led by one of the co-authors of the present work (36).…”

“…Different articles have been published that raise the hypothetical usefulness of nasal sprays with carrageenan for both prevention and treatment of COVID-19 (38)(39)(40), although some clinical trials are underway (Carrageenan Nasal Spray for COVID-19 Prophylaxis [ICE-COVID], Swansea University, ClinicalTrials.gov Identifier: NCT04590365; Prophylactic Treatment With Carragelose Nasal Spray to Prevent SARS-CoV-2, COVID-19, Infections in Health Care Workers, Marinomed Biotech AG, ClinicalTrials.gov Identifier: NCT04681001). So far, a unique trial has been completed, and its results published in a peer-reviewed journal indexed in PubMed (36). This pilot, pragmatic, multicenter, randomized, double-blind, and placebo-controlled study evaluates the efficacy of a nasal spray containing iota-carrageenan in the prophylaxis of COVID-19 in hospital personnel dedicated to the care of patients with COVID-19 (ClinicalTrials.gov Identifier: NCT04521322).…”