Krystal Biotech Doses First Patient in Phase III IOLITE Trial for KB803

Krystal Biotech has announced that the first patient has been dosed in IOLITE, the company’s Phase III clinical trial investigating KB803 for the treatment and prevention of corneal abrasions in patients with dystrophic epidermolysis bullosa (DEB).

A Gene Therapy Approach for DEB-Related Corneal Abrasions

KB803 is an innovative, redosable eye drop gene therapy designed to deliver two copies of the COL7A1 transgene directly to the epithelial cells of the eye. This therapeutic strategy targets the fundamental molecular mechanism driving disease in DEB patients, aiming to prevent and treat recurrent corneal abrasions—a common and painful complication of DEB.

Details of the IOLITE Trial

IOLITE (NCT07016750) is a double-blind, placebo-controlled, multicenter Phase III trial utilizing a crossover design. The study enrolls patients 6 months of age and older with DEB. Approximately 16 patients are expected to participate.

Each patient will initially receive a single eye drop of either KB803 (at a concentration of 10⁹ PFU/mL) or placebo to each eye once weekly for 12 weeks. Following this first period, patients will switch to the alternate treatment arm—placebo to KB803 or vice versa—for an additional 12 weeks of once-weekly administration. Notably, all drug administration will be performed in the patient’s home by a healthcare provider, reducing the need for frequent clinic visits.

Primary Endpoint and Study Assessments

The primary endpoint of IOLITE is the change in the average number of days per month with corneal abrasion symptoms while receiving KB803 compared to placebo. To account for expected high inter-patient variability, statistical analysis will focus on intra-patient paired measurements. Patients will complete weekly symptom diaries and monthly questionnaires to record corneal abrasion frequency and severity, as well as to capture impressions from patients or caregivers regarding disease changes throughout the study.