Development and Characterization of Inhaled Ethanol as a Novel Pharmacological Strategy Currently Evaluated in a Phase II Clinical Trial for Early-Stage SARS-CoV-2 Infection

Treatment with inhaled aerosolised ethanol reduces viral load and potentiates macrophage responses in an established influenza mouse model

AIM

Treatment options for viral lung infections are currently limited. We aimed to explore the safety and efficacy of inhaled ethanol in an influenza-infection mouse model.

MATERIALS AND METHODS

In a safety and tolerability experiment, 80 healthy female BALB/c mice (20 per group) were exposed to nebulized saline (control) or three concentrations of ethanol (40/60/80% ethanol v/v in water) for 3x30-minute periods, with a two-hour break between exposures. In a separate subsequent experiment, 40 Female BALB/c mice were nasally inoculated with 104.5 plaque-forming units of immediate virulence "Mem71" influenza. Infection was established for 48-h before commencing treatment in 4 groups of 10 mice with either nebulized saline (control) or one of 3 different concentrations of ethanol (40/60/80% ethanol v/v in water) for 3x30-minute periods daily over three consecutive days. In both experiments, mouse behavior, clinical scores, weight change, bronchoalveolar lavage cell viability, cellular composition, and cytokine levels, were assessed 24-h following the final exposure, with viral load also assessed after the second experiment.

RESULTS

In uninfected BALB/c mice, 3x30-minute exposures to nebulized 40%, 60%, and 80% ethanol resulted in no significant differences in mouse weights, cell counts/viability, cytokines, or morphometry measures. In Mem71-influenza infected mice, we observed a dose-dependent reduction in viral load in the 80%-treated group and potentiation of macrophage numbers in the 60%- and 80%-treated groups, with no safety concerns.

CONCLUSIONS

Our data provides support for inhaled ethanol as a candidate treatment for respiratory infections.

Effect of Ethanol Vapor Inhalation Treatment on Lethal Respiratory Viral Infection With Influenza A

Ethanol (EtOH) effectively inactivates enveloped viruses in vitro, including influenza and severe acute respiratory syndrome coronavirus 2. Inhaled EtOH vapor may inhibit viral infection in mammalian respiratory tracts, but this has not yet been demonstrated. Here we report that unexpectedly low EtOH concentrations in solution, approximately 20% (vol/vol), rapidly inactivate influenza A virus (IAV) at mammalian body temperature and are not toxic to lung epithelial cells on apical exposure. Furthermore, brief exposure to 20% (vol/vol) EtOH decreases progeny virus production in IAV-infected cells. Using an EtOH vapor exposure system that is expected to expose murine respiratory tracts to 20% (vol/vol) EtOH solution by gas-liquid equilibrium, we demonstrate that brief EtOH vapor inhalation twice a day protects mice from lethal IAV respiratory infection by reducing viruses in the lungs without harmful side effects. Our data suggest that EtOH vapor inhalation may provide a versatile therapy against various respiratory viral infectious diseases.

Positive Correlation Between Heavy Alcoholic Drinking and SARS-Cov-2 Non-Infection Rate

Introduction During the SARS-CoV-2 pandemic, rumors claimed that alcohol drinking could someway be useful in contrasting the contagion and even the disease. It appears opportune to bring some robust data to determine whether heavy alcohol drinkers and non-drinkers experienced different infection rates. Methods A cross-sectional study through a simple survey based on the social media software Weixin and the mini survey program Wenjuanxing was carried out in China after the zero-Covid policy ended, namely from 15:00 January 1, 2023, to 12:35 January 3, 2023. The evaluation was conducted among subjects belonging to the first author's Weixin community, mostly residents in the higher populated China area. Study participants received a questionary and were asked about their virus infection status, and were classified into two groups: (a) infected, meaning he/she has been infected at least once (whether recovered or not); (b) remain uninfected, meaning the virus has not infected him/her. A total of 211 subjects adhered to the survey. Alcoholic drinking behavior about liquors with no less than 40% alcohol content in volume was retrieved from the participants. In China, such beverages are almost uniquely referred to as the Chinese Spirits or BaiJiu. The frequency of drinking quantified the drinking behavior, and it is classified into three groups: never drink or drink occasionally (group A); drink one or two times per week (group B); drink three times per week or more often (group C). The hypothesis of an existing relationship between infection status and drinking behavior was advanced before data collection. The numbers of the uninfected people in each of the three drinking groups were counted, and the rates of not-infection were calculated. The rates are compared with each other to conclude whether significant differences exist, considering the size of the samples. The conclusion is drawn from standard hypothesis testing. Results The male/female ratio was 108/103 (51.2% and 48.8%), the mean age was 38.8 years (range 21-68), and the median age of 37.4 years. The total 211 participants fell into three groups with different drinking frequencies, with counts (percentages in total 211 participants) 139 (65.9%) in group A, 28 (13.3%) in group B, and 44 (20.8%) in group C. The number (percentage within the group) of uninfected members in groups A, B, and C are 29 (20.9%), 7 (25.0%), and 17 (38.6%), respectively. The statistical analysis through the Cochran-Armitage trend test gave a significative result: p=0.0209. Conclusions Within the methodology's limitations, this study shows the significant relationship between alcohol drinking habits and the chances of avoiding SARS-CoV-2 infection. A possible hypothesis explaining these findings is advanced. However, the authors warn about misleading conclusions and advocate research that could properly guide ethanol use in the present and other possible pandemics. Limitations This study is based on self-reported data from a specific community in China. There could be recall bias and social desirability bias, and the generalizability of the findings to other populations could be limited. Other factors that could influence infection rates, such as age, occupation, and health status, are not controlled in the present study. There could be other explanations for the observed relationship between alcohol drinking habits and infection rates.

Efficacy and Safety of Inhaled Ethanol in Early-Stage SARS-CoV-2 Infection in Older Adults: A Phase II Randomized Clinical Trial

BACKGROUND

Inhaled ethanol in the early stages of SARS-CoV-2 infection may reduce the viral load, decreasing progression and improving prognosis. The ALCOVID-19 trial was designed to study the efficacy and safety of inhaled ethanol in older adults at initial phases of infection.

METHODS

Randomized, triple-blind, placebo-controlled phase II clinical trial. Experimental group (n = 38) inhaled 65° ethanol through an oxygen flow, while in the control group (n = 37), water for injection was used. General endpoint was to evaluate disease progression according to the modified World Health Organization (WHO) Clinical Progression Scale. Specific effectiveness endpoints were body temperature, oxygen saturation, viral load assessed by cycle threshold (Ct) on real-time polymerase chain reaction (RT-PCR), analytical biomarkers and use of antibiotics or corticosteroids. Specific safety outcomes were the absence of ethanol in plasma, electrographic, analytical, or respiratory alterations.

RESULTS

In the intention-to-treat population, no differences were found regarding disease progression. Mean Ct values increased over time in both groups, being numerically higher in the ethanol group, reaching a value above 33 only in the ethanol group on day 14, a value above which patients are considered non-infective. No differences were found in the other specific effectiveness endpoints. Inhaled ethanol was proven to be safe as no plasma ethanol was detected, and there were no electrocardiographic, analytical, or respiratory alterations.

CONCLUSIONS

The efficacy of inhaled ethanol in terms of the progression of SARS-CoV-2 infection was not demonstrated in the present trial. However, it is positioned as a safe treatment for elderly patients with early-stage COVID-19.

Efficacy and Safety of Inhalation of Nebulized Ethanol in COVID-19 Treatment: A Randomized Clinical Trial

BACKGROUND

Coronavirus disease 2019 (COVID-19) is a pandemic caused by the SARS-CoV-2 virus. Many efforts have been made and are currently being made to prevent and treat this global disease.

OBJECTIVES

This study was designed to evaluate the efficacy and safety of nebulized ethanol (EtOH) in treating COVID-19.

METHODS

A randomized clinical trial (RCT) of 99 symptomatic and real-time polymerase chain reaction (RT-PCR)-positive patients admitted to a hospital receiving remdesivir-dexamethasone was conducted. They were randomly assigned to receive distilled water spray (control group (CG)) or 35% EtOH spray (intervention group (IG)). Both groups inhaled three puffs of spray (nebulizer) every six hours for a week. The primary outcome included Global Symptomatic Score (GSS) between the two groups at the first visit and on days three, seven, and 14. Secondary outcomes included the Clinical Status Scale (CSS; a seven-point ordinal scale ranging from death to complete recovery) and readmission rate.

RESULTS

A total of 44 and 55 patients were enrolled in the IG and CG, respectively. Although there was no difference at admission, the GSS and CSS improved significantly in the IG (p = 0.016 and p = 0.001, respectively). The IG readmission rate was considerably lower (0% vs. 10.9%; p = 0.02).

CONCLUSIONS

Inhaled-nebulized EtOH is effective in rapidly improving the clinical status and reducing further treatment. Due to its low cost, availability, and absent/tolerable adverse events, it could be recommended as an adjunctive treatment for moderate COVID-19. Further research on curative effects in more serious cases and in prevention is advisable.

The rationale of ethanol inhalation for disinfection of the respiratory tract in SARS-CoV-2-positive asymptomatic subjects

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic is a major health concern and is affecting the socio-economic lives. As other highly contagious diseases, it is of outmost importance to early identify and treat the healthy carriers or positive asymptomatic subjects (PAS). SARS-CoV-2 entry points are mainly in the respiratory tract. No specific virucidal treatments against SARS-CoV-2 are currently available. Monoclonal antibodies are under evaluation, but high cost and possible ineffectiveness against virus variants could limit its use. Resorting nonspecific drugs is an alternative approach. Among them, ethanol (EtOH) is known to be a powerful, cost-effective and abundant virucidal agent, now advised for surgical hand and surfaces disinfection. The paper aims to determine the potential role of inhaled ethanol to disinfect SARS-CoV-2 PAS, taking into account the dimension of the problem, ethanol efficiency and other beneficial effects on the respiratory tract, ethanol local and general toxicity and ethanol therapeutic window; consequently, to propose a study in order to verify this hypothesis. Together with the consolidated knowledge, an extensive review of the medical literature has been carried out looking for sound data able to support (or discard) the rationale on which a study could be built up. Evident data supporting the inhaled ethanol potential role on SARS-CoV-2 PAS disinfection have been found and discussed. A clinical trial to test the hypothesis that inhaled ethanol could be rapidly efficient in lowering or eradicating SARS-CoV-2 from the respiratory tract in PAS is advisable. Individual and public health benefits are stressed, together with socio-economic positive fallouts.