The safety and efficacy of alcaftadine 0.25% ophthalmic solution for the prevention of itching associated with allergic conjunctivitis.
OBJECTIVE
The purpose of this study was to evaluate the safety and clinical efficacy of alcaftadine 0.25% ophthalmic solution, a new topical anti-allergic agent for the prevention of the signs and symptoms of allergic conjunctivitis induced by conjunctival allergen challenge (CAC).


METHODS
This two-arm, double-masked, multi-center, placebo-controlled Phase III study (NCT00889330) enrolled healthy volunteers (N = 58) with a history of allergic conjunctivitis. Subjects ≥10 years of age with a reproducible, positive reaction to a CAC were randomized to receive either one drop of alcaftadine 0.25% ophthalmic solution bilaterally or vehicle bilaterally. After 16 hours (Visit 3) and 15 minutes (Visit 4), a CAC was performed and ocular and nasal symptoms of allergy were graded over a 20-minute period. Clinical and statistical significance were evaluated.


METHODS
The primary endpoints were ocular itching and conjunctival redness. The secondary endpoints were all other signs and symptoms of allergic conjunctivitis. Visual acuity, slit lamp biomicroscopy and adverse event reporting were the predetermined safety measures.


RESULTS
Alcaftadine was effective in the prevention of ocular itching based on both clinically relevant and statistically significant differences compared with vehicle (placebo). Alcaftadine significantly reduced conjunctival redness, and almost all other allergic signs and symptoms at both 15 minutes and 16 hours after drug administration. No significant safety issues were reported. Between-group differences in ocular itching were higher 16 hours after drug administration than at 15 minutes after drug administration.


CONCLUSIONS
With an onset of action within 3 minutes and a duration of action of at least 16 hours, the statistically and clinically significant effect of alcaftadine 0.25% on itching make it an important addition to therapy for ocular allergy. Additional studies are warranted to better understand the mechanisms affording a fast onset and prolonged duration of action.
Andover Eye Associates, Andover, MA 01810-1584, USA. mdlasik@comcast.net
Gail
G
Torkildsen
Arthur
A
Shedden
D000328:Adult; D001552:Benzazepines / Q000008:administration & dosage* / Q000009:adverse effects / Q000032:analysis; D003233:Conjunctivitis, Allergic / Q000150:complications / Q000188:drug therapy*; D004311:Double-Blind Method; D005260:Female; D006633:Histamine Antagonists / Q000008:administration & dosage / Q000009:adverse effects; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage* / Q000009:adverse effects / Q000032:analysis; D008297:Male; D008875:Middle Aged; D009883:Ophthalmic Solutions; D009994:Osmolar Concentration; D010919:Placebos; D011537:Pruritus / Q000209:etiology / Q000517:prevention & control*; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D001552:Benzazepines; D006633:Histamine Antagonists; D007093:Imidazoles; D009883:Ophthalmic Solutions; D010919:Placebos; C557708:alcaftadine