The prospective, multicentric, randomized, non-inferiority, controlled, open-label clinical investigation will evaluate the efficacy and safety of the use of Myrialen® gel vs.

Recugel®, two eye gel products containing 5% dexpanthenol, in patients with moderate to severe dry eye syndrome.

A total of 110 evaluable patients (55 in each treatment group), ≥18 years of age, will be required for data analysis. A total of 124 patients (62 in each treatment group) will be randomized to replace potential early withdrawals or non-evaluable patients.The primary objective of this investigation is to demonstrate non-inferior efficacy of Test Myrialen® gel over the Reference Recugel® in improving corneal and conjunctival surface state, assessed through slit lamp biomicroscopy examination, in patients with moderate to severe dry eye syndrome.

There is scarce documentation in literature on the effects of dexpanthenol in the management of DED. In a randomized, double-blind, placebo-controlled study that evaluated the effect of dexpanthenol-containing artificial tears in 50 patients with dry eyes, patients receiving the active ingredient had significant improvement of disturbances of the corneal epithelial permeability (as measured by fluorophotometry and Schirmer test, Rose Bengal staining, TFBUT), compared to the dexpanthenol-free eyes drops. Despite the scarce literature documentation, the use of 5% dexpanthenol, which stimulates the processes of reparative regeneration and possesses an anti-inflammatory effect, is actually considered as one of the promising directions in the management of patients with DED. Dexpanthenol has also been developed as a component of a contact lens system that controls its release as osmoprotectant and moisturizing agent with the aim to reduce symptoms of ocular dryness.

Based on this background, this investigation has been designed to compare the effects of the investigational device Myrialen® gel with another device containing 5% dexpanthenol, i.e. Recugel® eye gel, in the treatment of patients with moderate to severe dry eye syndrome. In particular, the main objective of this investigation is to demonstrate that the test device Myrialen®gel will be non-inferior to the reference device Recugel® in improving corneal and conjunctival surface state.

Inclusion Criteria:

1. Patient written informed consent to participate in the study obtained according to Good Clinical Practice (GCP);
2. Male and female patients aged ≥18 years;
3. Patients with new diagnosis of dry eye syndrome (according to Tear Film and Ocular Surface Society [TFOS] Dry Eye Workshop [DEWS] II definition), or previous diagnosis of dry eye syndrome not treated in the previous 15 days;
4. Diagnosis of dry eye syndrome performed through the following exams: slit lamp examination (SLE), Impact of Dry Eye on Everyday Living (IDEEL) questionnaire, tear (lacrimal) meniscus exam, Schirmer's test, Tear Film Break-Up Time (TFBUT), fluorescein and lissamine green staining of the cornea and conjunctiva (respectively). In case of bilateral dry eye syndrome, only the worst eye, defined as the eye with the higher severity of impairment according to theInvestigator's judgment based on the above exams, will be considered for assessments (although both eyes will be treated). In the case of bilateral dry eye syndrome with both eyes having the same level of impairment, the right eye will be considered for assessments by convention;
5. Sodium fluorescein and lissamine green staining score of the cornea and conjunctiva(respectively) ≥ 2 National Eye Institute (NEI) grid, defined as the sum of 5 areas per eye using a 0 (normal) to 3 (severe) scale) in the worst eye for the corneal staining and the sum of 6 areas per eye using a 0 (normal) to 3 (severe) scale in the worst eye for the conjunctival staining;
6. A Schirmer test value < 10 mm;
7. A TFBUT value ≥ 5 sec;
8. Patient able to comprehend the full nature and the purpose of the study, including possible risks and side effects, and subjects able to cooperate with the Investigator and to comply with the requirements of the entire study (including ability to attend all the planned study visits according to the time limits), based on Investigator's judgment;
9. Females of childbearing potential (i.e., not permanently sterilised - post hysterectomy or tubal ligation status - or not postmenopausal for at least one year) must have a negative urine pregnancy test result at Screening and must use an appropriate method of contraception for at least 30 days before inclusion in the study and during the whole study period, according to the definition in ICH M3 Guideline:

A highly effective method is defined as that which results in a low failure rate (i.e., less than 1% per year) when used consistently and correctly. Highly effective birth control methods include:

combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation (oral, intravaginal, transdermal); progestogen-only hormonal contraception associated with inhibition of ovulation (oral, injectable, implantable); intrauterine device (IUD); intrauterine hormone-releasing system (IUS); bilateral tubal occlusion; vasectomised partner; sexual abstinence.

Exclusion Criteria:

1. Any ocular disease other than dry eye syndrome requiring treatment with ophthalmological topical medications with re-epithelizing, trophic, anti-infective or anti-inflammatory effect (e.g. antibiotics, corticosteroids, gel re-epithelizing, platelet-rich plasma, autologous serum, medication with vitamin A, hyaluronic acid-based products) in either eye at the time of study enrolment and in the previous 30 days;
2. Any active ocular infection or active inflammation in either eye unrelated to dry eye syndrome;
3. Presence or history of any systemic or ocular disorder, condition or disease (with particular attention to malignancies and neuro-oncological diseases) that, according to Investigator's judgment, can interfere with the conduct of the required study procedures or the assessment of the efficacy or the interpretation of the study results or the incidence of adverse events;
4. Use of therapeutic or refractive contact lenses in either eye in the previous 20 days and at the time of study enrolment;
5. History of ocular surgery in either eye, excluding corneal refractive or cataract procedures, within 90 days of study enrolment;
6. Treatment with any other therapy that, according to Investigator's judgment, could interfere with the assessment of the efficacy or incidence of adverse events;
7. Hypersensitivity and/or allergy to any of Myrialen® gel and/or Recugel® ingredients;
8. Women pregnant or breastfeeding or women who could become pregnant and are not using effective contraception;
9. Patients unlikely to comply with the protocol or unable to understand the nature, scope and possible consequences of the investigation;
10. Participation in another clinical investigation within the past 30 days or previous enrolment in this investigation.