Testing the Efficacy in Adults With Cold of HEalsea Rescue*

Healsea® Rescue\* is a CE-marked class I medical device. This is a saline-based nasal spray supplemented with a natural Symbiofilm™ extract (0.04%) isolated from the marine bacteria. Healsea® Rescue\* is indicated in adults for the treatment of symptoms of acute respiratory tract infections, rhinitis or rhinosinusitis, and for reduction of the swelling of the nasal mucosa.

The goal of this clinical trial is to demonstrate that hypertonic saline solution and Symbiofilm™ act in a synergistic manner to alleviate symptoms of the acute rhinitis phase resulting in better efficacy than isotonic saline solution without Symbiofilm™ used as Placebo in adults with early symptoms of common cold / acute infectious rhinitis.

Upper respiratory tract infections (URTIs) and sino-nasal symptoms are very frequent, especially during the fall and the winter. The common cold is caused by a variety of viruses such as human rhinoviruses and influenza viruses. The incidence of acute rhinitis/rhinosinusitis is very high, estimated to occur from 2 to 5 times per year in the average adult. However, the natural course of acute rhinitis in adults is favorable since 75% of persons have a reduction or resolution of symptoms within 7 days. Only 0.5 to 2.0% of subjects develop secondary bacterial sinusitis requiring antibiotic prescription. Bacterial over infections and progression to a chronic state are favoured by the formation of biofilms, which facilitate bacterial growth and persistence as well as reducing antibiotic efficacy. The socioeconomic impact of acute rhinitis is well established: visits to GP, additional prescriptions and over prescription of antibiotics, workdays lost.

Although clinical evidence from well-designed trials is scarce, European and American guidelines for acute rhinosinusitis recommend daily nasal saline irrigation for reduction of the severity of symptoms and for speeding recovery. The exact mechanisms by which nasal irrigation works are not known. However, most of the experts agree that it is primarily a mechanical intervention leading to direct cleansing of the nasal mucosa. Hypertonic saline solutions are generally considered as more effective than isotonic saline solutions in reducing nasal symptoms in the acute phase. Nevertheless, the efficacy of such solution remains moderate.

Healsea® Rescue\* is a CE-marked class I medical device. This is a saline-based nasal spray supplemented with a natural Symbiofilm™ extract (0.04%) isolated from the marine bacteria Bacillus licheniformis T14. The nasal solution is hypertonic (NaCl 2.7%). Symbiofilm™ is an exopolysaccharide with emulsifying properties and in vitro antibiofilm activity and detachment properties against various bacterial pathogens. Symbiofilm™ also protects in vitro human nasal epithelial cells viability after Rhinovirus, Adenovirus, Coronavirus OC43 and Flu infection.

The aim of this study is to demonstrate that hypertonic saline solution and Symbiofilm™ act in a synergistic manner to alleviate symptoms of the acute rhinitis phase resulting in better efficacy than isotonic saline solution without Symbiofilm™ used as Placebo.

The study comprises two parts:

- Part 1 (Day1-Day 8): treatment of the acute phase

• with Healsea® Rescue\*, 2 puffs in each nostril 2 times per day during 7 days (14 intakes of the investigational device).

or • with isotonic nasal spray (Placebo), 2 puffs in each nostril 2 times per day during 7 days (14 intakes of the Placebo).

- Part 2 (Day 9-Day 13/15): follow-up phase.

The study comprises two visits and one telephone call:

* Visit 1 (V1) at Day 1
* Telephone call at Day 8
* End of study visit (Visit 2, V2) between Day 13 and Day 15.

Eligibility Criteria:
Inclusion Criteria:

1. Male/Female subjects \>18 years
2. Acute infectious rhinitis/rhinosinusitis for ≤48h before trial entry
3. Symptoms of headache, muscle ache, chilliness, sore throat, blocked nose, runny nose, cough, sneezing with a score ≤9 (according to a self-rated symptom score; scale: 0 → 3 \[0: no symptom to 3: severe intensity\])
4. At least one of these symptoms: sore throat, runny nose or blocked nose (i.e., with a score ≥1)
5. Willingness to participate as evidenced by voluntary written informed consent and has received a signed and dated copy of the information consent form
6. Patient with a smartphone and an internet connection.

Exclusion Criteria:

1. Known hypersensitivity/allergy to any component of the test device
2. Medical history or any current disease that is considered by the investigator as a reason for non-inclusion
3. Severe nasal septum deviation or other condition that could cause nasal obstruction such as the presence of nasal polyps
4. History of nasal or sinus surgery that in the opinion of the investigator may influence symptom scores
5. Antibiotic intake within 2 weeks before screening
6. Systemic or local corticosteroids (nasal route or inhalation) within 4 weeks before screening
7. Antihistamines intake for allergy when treatment was started from less than 4 weeks
8. Chronic decongestant use
9. Recent (within the previous 2 days) intake of a common cold medicine that in the opinion of the investigator may influence symptom score at screening (NSAID, nasal decongestants, cough medicines)
10. Pregnant/Lactating female or absence of efficient contraception