Patients
Patients aged 18 to 65 years were selected for eligibility based on having a history of >2 years of moderate allergic conjunctivitis during birch pollen season.1, 11Allergic sensitizations were documented by a positive skin prick test to birch allergen with a wheal diameter ≥ 6 mm compared to negative control and positive birch-specific IgE (> 0.10 kU/l). The main inclusion criterion was a positive conjunctival response during an individual conjunctival allergen challenge.10, 11 The study was performed outside the pollen season in France. A 7‐day washout period was required for topical or systemic anti‐histamines or other ophthalmic treatment. Exclusion criteria were evaluated prior to inclusion and were as follows: patients experiencing a single ocular symptom in the previous week; patients who received long‐acting corticosteroids within the past 4 weeks; ocular laser treatment within the past 3 months; ocular surgery within the last 6 months; abnormality or clinically significant ocular disorder, including symptoms of allergic conjunctivitis; ongoing immunotherapy to any allergen or, within the last 5 years, to birch allergen.