Krystal Biotech Announces FDA Acceptance of KB407 IND Application for Cystic Fibrosis Clinical Trial

Krystal Biotech, Inc. announced that the United States Food and Drug Administration (FDA) has accepted its Investigational New Drug (IND) application to evaluate KB407 in a clinical trial for cystic fibrosis (CF).

KB407 is a modified HSV-1 vector carrying two copies of the cystic fibrosis transmembrane conductance regulator (CFTR) gene to the respiratory cells in the lungs. By inducing expression of full length, normal CFTR protein in the lung, treatment with KB407 has potential to restore ion and water flow into and out of lung cells to correct the lung manifestations of the disease in patients regardless of their underlying genetic mutation.

CF is a genetic disease, affecting people of every racial and ethnic group, by causing a buildup of mucus in the lungs leading to persistent lung infections and progressive pulmonary disease. Sources including the Cystic Fibrosis Foundation indicate that there are close to 40,000 children and adults living with cystic fibrosis in the US, and an estimated 105,000 people diagnosed with CF across 94 countries.

“We are excited to advance KB407, our investigational gene therapy for patients with CF, into the clinic. It is designed to treat the root cause of the disease regardless of an individual patient’s mutation by giving the body instructions to produce its own functional protein,” said Hubert Chen, M.D., Senior Vice President of Clinical Development at Krystal Biotech. Dr. Chen continued, “In addition, this IND acceptance represents an important milestone for us as it allows us to demonstrate the power of our platform to deliver genes, beyond skin cells, to respiratory cells.”

On July 1, 2022, the Company submitted an IND application to initiate the Phase 1 clinical trial of KB407. At the end of the 30-day review period, the Company received notification that the FDA accepted the IND allowing the Phase 1 clinical trial to begin. The Company anticipates initiating the clinical trial in 2H 2022.

Phase 1 Trial Overview
The Phase 1 clinical trial will utilize nebulized administration to deliver KB407 in up to 20 adults with CF. The study will enroll 3 cohorts sequentially to evaluate ascending doses of KB407. The primary endpoint of the trial will be the safety and tolerability of nebulized KB407. Changes in lung function from baseline will be assessed by forced expiratory volume in one second.