Efficacy and safety of a new ophthalmic preservative‐free formula of levocabastine 0.05% during a conjunctival allergen challenge

Purpose To evaluate the efficacy and safety of preservative‐free levocabastine 0.05% ophthalmic solution (PFL) compared to preserved levocabastine 0.05% ophthalmic suspension (PL) and vehicle of the solution in the prevention of allergic conjunctivitis induced by a conjunctival provocation test (CPT). Methods 92 healthy volunteers with a history of allergic conjunctivitis were randomized in this double‐masked study. 69 subjects received 1 drop of PFL in 1 eye and 1 drop of PL in the fellow eye, either 10 min [visit 3 (V3)] or 4 h [visit 4 (V4)] prior to CPT. 23 subjects received 1 drop of PFL in 1 eye and 1 drop of vehicle in the fellow eye, either 10 min or 4 h prior to CPT. The primary endpoint was the sum score of itching and redness assessed 3, 5 and 10 min after CPT at V3 and at V4. Other evaluations included tolerance, corresponding to study drug drop sensation and adverse events. Results PFL was shown to be statistically superior to vehicle (p ≤ 0.01) at all time points with one exception at V4, 3 min after CPT. Sum scores varied from 0.7 to 1.6 with PFL and from 1.2 to 2.7 with vehicle. PFL was shown to be statistically superior to PL at V3 and non‐inferior at V4. At V3, the sum scores varied from 0.7 to 1.6 with PFL and from 1.2 to 2 with PL. At V4, sum scores varied from 1.1 to 1.7 with PFL and from 0.9 to 1.7 with PL. Upon instillation, PFL was better tolerated than PL (p<0.001). No serious adverse events were recorded. Conclusion The efficacy of the preservative‐free solution of levocabastine is superior to the effect of the vehicle and, at V3, superior to the efficacy of the preserved suspension of levocabastine. The preservative‐free solution was better tolerated than the preserved suspension.Commercial interest