Common colds incur significant costs in terms of sick leave and personal discomfort for affected individuals. This study investigated the performance of ColdZyme® Mouth Spray (ColdZyme), a protective barrier against common cold, in rhinovirus-inoculated healthy volunteers. This randomized, doubleblind, placebo-controlled pilot study was conducted on 46 healthy volunteers inoculated with rhinovirus 16 via the nose. Subjects self-administered ColdZyme or placebo 6 times daily for 11 days. Symptoms were recorded daily in a diary. Rhinovirus 16 in nasal and oropharyngeal samples at days 0, 3, 4, 6, 7 and 10 were quantified by RT-qPCR. The primary outcome measure was the reduction in viral load in oropharyngeal samples. Rhinovirus 16 was only detected in 35 out of 46 inoculated subjects. Exploratory analysis measuring the total viral load (i.e., area under the curve (AUC)) for days 3 -10 in successfully inoculated subjects found that ColdZyme treatment resulted in a lower total viral load in the oropharynx (p = 0.023). In subjects who experienced symptomatic common cold, irrespectively, if virus were detected, treatment with ColdZyme resulted in a reduction in the number of days with common cold symptoms from 6.5 to 3.0 days (p = 0.014) in comparison to placebo. ColdZyme reduced virus infection in the oropharynx and reduced the number of days with common cold symptoms and highlights the possible importance of the oropharynx in common cold infections. Suitable outcome measures for a feasible study on ColdZyme are total viral load in the oropharynx in subjects having detectable virus present in nasal or oropharyngeal samples.

The medical device ColdZyme is a mouth spray that forms a barrier in the throat against common cold viruses. The barrier solution of the device is composed of glycerol and Atlantic cod trypsin. The aim of this study was to evaluate the virus deactivating ability of ColdZyme against four major common cold viruses. A virucidal efficacy suspension test was conducted using ColdZyme against each of the challenge viruses in suspension. ColdZyme deactivated rhinovirus type 1A by 91.7% (1.08 log 10 ), rhinovirus type 42 by 92.8% (1.14 log 10 ), human influenza A virus H3N2 by 96.9% (1.51 log 10 ), respiratory syncytial virus (RSV) by 99.9% (2.94 log 10 ) and adenovirus type 2 by 64.5% (0.45 log 10 ). Based on the results, ColdZyme showed an effective broad-spectrum impact against common cold viruses. Thus, ColdZyme might represent a device with clinical benefits in prevention and treatment of respiratory viral infections by deactivating viruses within the respiratory tract.

Proteases have been used in medicine for several decades and are an established and well tolerated class of therapeutic agent. These proteases were sourced from mammals or bacteria that exist or have adapted to moderate temperatures (mesophilic organisms); however, proteases derived from organisms from cold environments—cold-adapted or psychrophilic proteases—generally have high specific activity, low substrate affinity, and high catalytic rates at low and moderate temperatures. Made possible by greater flexibility, psychrophilic enzymes interact with and transform the substrate at lower energy costs. Cold-adapted proteases have been used in a wide range of applications, including industrial functions, textiles, cleaning/hygiene products, molecular biology, environmental bioremediations, consumer food products, cosmetics, and pharmaceutical production. In addition to these applications, they have also shown promise as therapeutic modalities for cosmeceutical applications (by reducing glabellar [frown] lines) and a number of disease conditions, including bacterial infections (by disrupting biofilms to prevent bacterial infection), topical wound management (when used as a debridement agent to remove necrotic tissue and fibrin clots), oral/dental health management (by removing plaque and preventing periodontal disease), and in viral infections (by reducing the infectivity of viruses, such as human rhinovirus 16 and herpes simplex virus). Psychrophilic proteases with greater activity and stability (than the original organism-derived variant) have been developed; this coupled with available manufacturing recombinant production techniques suggests that cold-adapted proteases have a promising future as a distinct therapeutic class with diverse clinical applications.

ColdZyme® Mouth Spray (ColdZyme) is a mouth spray intended to reduce the probability of catching a cold and/or can help shorten the duration of a cold if used at an early stage of the infection, by forming a barrier on the pharyngeal mucous membrane. This study evaluated the preventative effect of ColdZyme on common cold infections in personnel at elderly care facilities, and assessed the level of reduction in corresponding sick leave. The number of sick-leave days for the personnel decreased from an average of 5.2 days to 3.7 days (29%) when using ColdZyme compared to control period (p = 0.054). 63% of those who had a cold reported the symptoms to be milder than previous colds. Conclusion: Using ColdZyme® Mouth Spray to apply a barrier to the oropharynx may be an easy and practical way to prevent or reduce infections of the common cold virus and corresponding sick leave in personnel working in elderly care.

The common cold is one of the most frequently encountered infectious diseases in humans and, despite the modest severity in most cases; it presents a significant economic burden upon society and individuals. ColdZyme® Mouth Spray (ColdZyme®, Enzymatica AB, Lund, Sweden) is a mouth spray intended to reduce the probability of catching a cold and can also help shorten the duration of a cold if used at an early stage of the infection, by forming a barrier on the oropharyngeal mucous membrane. This study evaluated the effect of ColdZyme® on common cold related sick-leave in preschool (kindergarten) staff. Fifteen preschool staff members were evaluated over a 6-month period and ColdZyme® was used according to instructions. Sick-leave days were recorded and compared to historical data. The number of average sick leave days decreased during the period from 7.4 days to 4.1 days (p = 0.04). It is notable that, if occurring, the majority of subjects perceived a common cold infection as milder than usual. Conclusion: Using ColdZyme® to apply a barrier to the pharyngeal mucous membrane may be an easy and practical way to prevent or reduce infections and corresponding sick leave in personnel from the preschool environment.