In two parallel clinical trials, an antihistamine-releasing contact lens reduced symptoms in patients with allergic conjunctivitis.
Two hundred forty-four subjects were randomly assigned to be fitted with ketotifen-containing lenses in one or both eyes or control lenses. All subjects were contact lens users with a positive history of ocular allergies and a positive skin test reaction to cat hair, cat dander, grass, ragweed or trees. Patients underwent allergen challenges and responses were evaluated at 15 minutes and 12 hours after lens insertion for subjective itching symptoms and objective signs of ciliary, conjunctival and episcleral redness.
The mean itch score, on a scale from 0 to 4, was significantly lower in the eyes with ketotifen-containing lenses at all time points. Differences in redness score were not statistically significant.
Contact lens drug delivery can potentially improve compliance to both anti-allergic medications and contact lens use in patients with allergic conjunctivitis, the authors noted. Patients tend to revert to spectacles during the allergy season because contact lenses exacerbate symptoms and may cause damage to the ocular surface with eye rubbing. In addition, topical anti-allergic medications normally require administration after removing the contact lens.
“Combining vision correction and therapeutic treatment for allergy increases compliance for both conditions by simplifying overall management,” the authors wrote.
Furthermore, confined between the lens and the ocular surface, the drug is compartmentalized and shielded from the washout effect of blinking and may therefore have longer duration.
“By combining a CL and a drug such as ketotifen, allergy sufferers who wear lenses can receive reliable daily allergy relief that lasts for as long as they typically wear the CLs, while avoiding potential adverse effects of preservatives commonly found in topical ocular preparations,” the authors wrote. – by Michela Cimberle
Disclosures: Pall reports he is from Johnson & Johnson Vision, which funded the studies. Please see the study for all other authors’ relevant financial disclosures.