Castle Biosciences has announced its investigational gene expression profile test for atopic dermatitis (AD) may identify patients likely to achieve a 90% or greater reduction in Eczema Area and Severity Index (EASI) scores within three months of targeted therapy initiation.
Currently, over six million individuals in the U.S. are diagnosed with moderate-to-severe AD annually, with approximately 760,000 seeking systemic treatment. The prevalent 'trial-and-error' approach in selecting systemic therapies leads to about 25% of patients discontinuing initial treatments, while around 50% of those continuing experience persistent disease burden, according to a Castle news release about the announcement.
"Data from our ongoing validation study for our pipeline test suggests we may be able to improve the standard-of-care 'trial-and-error' treatment approach by identifying patients who are more likely to achieve a super response to a specific class of therapy based on identification of the immune pathway that is driving their AD," said Derek Maetzold, president and CEO of Castle Biosciences, in a news release from the manufacturer. "Using a molecular test to identify the disease-driving immune pathways and to inform the class of drugs a patient could initiate based on increased likelihood of achieving a super response provides a precision medicine tool to increase the number of patients achieving a super response in less time by reducing ‘trial-and-error,’ which may reduce the utilization of healthcare resources.”
The test 'aims to pinpoint the immune pathways driving an individual's AD, thereby guiding clinicians in selecting the most effective class of systemic therapy,' according to the manufacturer. The test aligns with endpoints used in current drug development by focusing on predicting a 90% or greater reduction in disease severity (EASI90) within three months, potentially expediting patient response and reducing use of healthcare resources.
Castle said that it has enrolled over 1,100 patients across 39 clinical study sites in its prospective development and validation study as of September 2024. Pending validation, the company anticipates launching the test in late 2025.