This study is a prospective, multicentre, parallel-group, active-controlled, non-inferiority study conducted in adult patients with moderate-to-severe dry eye disease (DED) related to keratitis or keratoconjunctivitis. This study is to be conducted in France, Poland and Spain.

The patients will be randomised to receive Cationorm Pro® or the reference treatment, VISMED® (ratio 1:1) in an investigator-masked fashion

Primary:

• To compare the ocular efficacy of Cationorm Pro® with that of VISMED® in patients with moderate to severe DED related to keratitis or keratoconjunctivitis after a 4-week treatment period (Day 28).

Secondary:

To compare the ocular efficacy of Cationorm Pro® with that of VISMED® in patients with moderate to severe DED related to keratitis or keratoconjunctivitis over a 12-week treatment period To evaluate the ocular tolerability and safety of Cationorm Pro® versus VISMED® in patients with moderate to severe DED related to keratitis or keratoconjunctivitis throughout the duration of treatment

Inclusion Criteria:

1. Male or female patient aged 18 years or above.

2. Patient using artificial tears for at least 3 months prior to the Screening visit.

3. Patient experiencing at least 2 symptoms of ocular discomfort rated ≥23 mm on the 0 to 100 mm visual analogue scale (VAS) (among itching, eye dryness, sticky feeling, photophobia, pain, burning or stinging, sandy feeling or grittiness, or foreign body sensation) at Screening and Baseline visits.

4. OSS score (sum of nasal and temporal interpalpebral conjunctival and corneal vital staining) ≥4 and ≤9 on a modified Oxford scale at Screening and Baseline visits in at least one eye.

5. TBUT of ≤10 seconds at Screening and Baseline visits and/or Schirmer's tear test of ≥3 and ≤9 mm/5 min at Screening visit in the same eye that fulfil inclusion criteria #4.

6. The patient has signed and dated a written informed consent form prior to the initiation of any study procedures.

   -

Exclusion Criteria:

the study: Ocular

1. CFS score ≥4 on a modified Oxford scale
2. Ocular hypertension or glaucoma requiring IOP-lowering medication(s)
3. History of ocular trauma, infection or ocular inflammatory condition within the last 3 months before the screening visit.
4. Severe blepharitis and/or severe meibomian gland disease
5. Filamentary keratitis
6. Any ocular surface anomaly not related to DED
7. Active ocular infection or history of ocular allergy or ocular herpes
8. Patient with only one sighted eye or with a best corrected distance visual acuity ≤1/10
9. Use of any topical ocular treatment other than study device during the study (all non-study topical ocular treatment(s) must be stopped at the screening visit)
10. Onset of lid hygiene (whatever the method) less than 2 months before the Screening visit
11. Use of topical corticosteroids one month before the Screening Visit
12. Use of isotretinoin, ciclosporin, tacrolimus, sirolimus, pimecrolimus or ocular cauterisation procedures 2 months before the screening visit and throughout the study
13. Use of VISMED® within 6 weeks prior to the screening visit
14. Refractive surgery (e.g. LASIK, LASEK, PRK) within 6 months and/or any other ocular laser/surgery within 3 months prior to the screening visit and during the study
15. Insertion of temporary punctal plug(s) within 2 months prior to the Screening visit or permanent occlusion of lacrimal puncta on one or both sides
16. Known hypersensitivity to any of the components of the study device or investigational products Non-ocular
17. History of severe systemic allergy
18. Systemic disease not stabilised within 1 month prior to the screening visit (e.g. diabetes with glycaemia out of range, thyroid dysfunction) or judged by the investigator to be incompatible with the conduct of the study procedures or the interpretation of the study results
19. Any change of systemic concomitant medication within the month before the screening visit or planned change during the study period, except paracetamol
20. Pregnancy or lactation at the screening and/or Baseline visit.
21. Women of childbearing potential not using a medically acceptable, highly effective method of birth control (such as hormonal implants, injectable or oral contraceptives together with condoms, some intrauterine devices, sexual abstinence or vasectomised partner) from the Baseline visit throughout the conduct of the study treatment periods and up to 2 weeks after the study end. Post-menopausal women (two years without menstruation) do not need to use any method of birth control.
22. Participation in a clinical trial with an investigational substance within the past 30 days prior to Baseline visit.
23. Participation in another clinical study at the same time as the present study. -

Investigator Masked, unmasked Pharmacist