Sjögren's syndrome is a condition in which the immune system attacks the body's moisture-producing glands. This often causes severe dry eye, leading to discomfort, irritation, blurred vision, and damage to the eye surface. Inflammation plays an important role in this process, and a protein called TNF-alpha is one of the key drivers.

This study will test a new eye drop containing infliximab, a medication that blocks TNF-alpha. The goal is to see whether this treatment can safely improve symptoms and signs of severe dry eye in patients with Sjögren's syndrome.

Sjögren's syndrome is a condition in which the immune system attacks the body's moisture-producing glands. This often causes severe dry eye, leading to discomfort, irritation, blurred vision, and damage to the eye surface. Inflammation plays an important role in this process, and a protein called TNF-alpha is one of the key drivers.

This study will test a new eye drop containing infliximab, a medication that blocks TNF-alpha. The goal is to see whether this treatment can safely improve symptoms and signs of severe dry eye in patients with Sjögren's syndrome.

Inclusion Criteria:

• Adult patients (≥ 18 years).
• Confirmed diagnosis of primary or secondary Sjögren's syndrome according to the 2016 ACR/EULAR classification criteria.
• On stable systemic immunomodulatory therapy (non-biologic) for at least 12 weeks, with no planned changes during the study (see section 14.1 if there are concerns about confounding variables).
• Negative chest X-ray or Interferon-Gamma Release Assays (IGRA).
• Diagnosis of severe dry eye, defined by meeting all of the following criteria in at least one eye at study entry:
• OSS (SICCA 0-12) ≥ 6 in at least one eye.
• OSDI ≥ 33 (severe symptoms).
• Symptoms: OSDI score ≥ 33.
• Signs: Ocular Staining Score (OSS, SICCA) ≥ 6.
• Ability to understand and sign informed consent and to comply with study procedures and treatment administration.

Exclusion Criteria:

• Current use of topical corticosteroids or topical immunomodulators (cyclosporine, lifitegrast, tacrolimus, autologous serum) within 30 days prior to enrollment.
• Current or recent use (< 3 months) of punctal plugs.
• Active ocular infection (bacterial, viral, fungal) or recent history of herpetic keratitis.
• Ocular or eyelid surgery within the past 6 months.
• Use of contact lenses during the study period.
• Known allergy or hypersensitivity to infliximab, murine proteins, or any component of the formulation (including CMC).
• Coexisting ocular conditions that may interfere with dry eye evaluation (e.g., active ocular cicatricial pemphigoid, active ocular graft-versus-host disease, uncontrolled glaucoma, significant corneal dystrophy).
• Systemic conditions considered contraindications to infliximab exposure, including: active systemic infection, untreated active or latent tuberculosis, history of demyelinating disease, moderate to severe congestive heart failure (NYHA Class III/IV), or history of malignancy within the past 5 years.
• Use of systemic biologic agents within the past 6 months (12 months for systemic anti-TNF-α therapy).
• Pregnancy, breastfeeding, or intention to become pregnant during the study.
• Participation in another clinical trial with an investigational drug within the past 30 days.
• Ability to understand and sign informed consent and to comply with study procedures and treatment administration.