Can An Allergy Spray Help Prevent Covid-19?

An mundane allergy spray lowered coronavirus and acold infections successful a objective trial, sparking liking successful its imaginable arsenic a simple, over-the-counter defense against respiratory viruses.

Study: Azelastine Nasal Spray for Prevention of SARS-CoV-2 Infections: A Phase 2 Randomized Clinical Trial. Image Credit: Ground Picture / Shutterstock.com

Despite wide vaccination rates and established organization immunity, nan terrible acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to mutate and move passim nan environment. This emphasizes nan captious request for effective prophylactic therapies, peculiarly for high-risk groups for illustration nan aged and immunocompromised.

In a caller study published successful nan JAMA Internal Medicine, researchers wished nan efficacy and information of azelastine 0.1% nasal spray successful a shape 2 double-blind, placebo-controlled randomized objective proceedings for preventing SARS-CoV-2 infection successful patient adults.

Evaluating azelastine arsenic prophylaxis against COVID-19

Azelastine is simply a histamine H1-receptor antagonist wide disposable arsenic an over-the-counter nasal spray for managing allergies. Recent studies propose that azelastine exhibits antiviral activity against respiratory syncytial microorganism (RSV) and influenza A (H1N1), pinch respective randomized objective tests confirming reductions successful SARS-CoV-2 viral load erstwhile utilized to dainty COVID-19.

In nan existent study, researchers conducted a double-blind, placebo-controlled randomized objective proceedings astatine Saarland University Hospital to measure azelastine arsenic a prophylactic measurement against SARS-CoV-2. Healthy adults betwixt 18 and 65 years of property pinch antagonistic accelerated antigen trial (RAT) results were randomized to usage either azelastine nasal spray aliases placebo 3 times each time for 56 days. If a high-risk vulnerability occurred aliases symptoms were detected, study participants were advised to summation their dose to 5 times/day for 3 days.

Twice-weekly nasopharyngeal RATs were performed, pinch each affirmative results confirmed by reverse-transcriptase polymerase concatenation guidance (RT-PCR) assay. Symptomatic participants pinch antagonistic RAT results were besides subsequently tested utilizing RT-PCR assay and a multiplex respiratory sheet for rhinovirus, influenza, endemic coronaviruses, RSV, quality metapneumovirus (HMPV), adenovirus, and Mycoplasma pneumoniae, and different pathogens, including parainfluenza, bocavirus, enterovirus, and parechovirus.

The superior endpoint was PCR-confirmed SARS-CoV-2 infection passim nan study period. Secondary extremity points included symptomatic infection, clip to infection, long of RAT positivity, non-SARS-CoV-2 infections, and adverse events (AEs) coded pinch nan Medical Dictionary for Regulatory Activities (MedDRA).

Secondary outcomes were not adjusted for multiplicity, and immoderate sensitivity analyses mislaid statistical value nether definite imputations, though nary script favored placebo. All analyses utilized intention-to-treat (ITT) and per-protocol (PP) sets pinch statistic and time-to-event models.

Clinical efficacy and information results

A full of 450 participants were included successful nan study, 227 and 223 of whom were treated pinch azelastine aliases placebo, respectively. Throughout nan study period, PCR-confirmed SARS-CoV-2 infection was reported successful 2.2% of azelastine recipients arsenic compared to 6.7% of those successful nan placebo group, pinch a consequence quality (RD) of -4.5 percent points and an likelihood ratio (OR) of 0.31.

The time-to-event study indicated that azelastine curen reduced nan hazard of infection (hazard ratio 0.31). Among infected participants, nan mean clip to infection was longer pinch azelastine than pinch placebo, astatine 31.2 and 19.5 days, respectively. Symptomatic SARS-CoV-2 infections were little predominant pinch azelastine, astatine 1.8%, arsenic compared to placebo, astatine 6.3%.

The mean long of RAT positivity was shorter pinch azelastine curen astatine 3.40 days compared to 5.14 days among placebo recipients. Across each laboratory-confirmed respiratory infections, 8.4% of azelastine users tested affirmative compared to 18.8% of study participants successful nan placebo group.

Human rhinovirus was nan astir predominant non-SARS-CoV-2 pathogen to infect study participants. However, its incidence was little pinch azelastine curen than pinch placebo, astatine 1.8% and 6.3%, respectively. Reduced cumulative unwellness days were besides little passim nan study period.

About 52% of study participants reported astatine slightest 1 AE pursuing azelastine treatment, compared to 50.7% pinch a placebo. Some of nan different AEs associated pinch azelastine curen included bitter taste, epistaxis, and fatigue, each known broadside effects of topical antihistamines.

Treatment discontinuation owed to AEs were uncommon astatine 0.9% and 0.5% for azelastine and placebo, respectively. Two superior AEs were reported successful nan azelastine group, of which included recurrent headache that required infirmary information and caller Hashimoto thyroiditis.

Potential sources of bias included reliance connected RAT results to initiate further testing, missed discovery of asymptomatic infection, and partial unblinding related to nan bitter taste. Placebo hypromellose whitethorn person besides led to insignificant obstruction effects, which further dilutes between-group differences.

Clinical implications

Regular usage of azelastine nasal spray was associated pinch less laboratory-confirmed SARS-CoV-2 infections and less wide respiratory infections. Importantly, these results were based connected a single-center proceedings successful mostly patient and vaccinated adults pinch debased arena counts and measurement biases. Larger, multicenter studies are needed crossed divers ages, consequence profiles, and viral seasons to corroborate effectiveness, refine optimal dosing schedules, and qualify benefits against different respiratory pathogens.