Company: CSTL
Filing Date: 2025-02-27
Form Type: 10-K
Source: 0001447362-25-000031
Chunk: 50

Company: CASTLE BIOSCIENCES INC
Filing Date: 2025-02-27
Form: 10-K
Item: Item 1
Chunk 50
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 (“AltheaDx”) in April 2022.

IDgenetix is supported by a published, peer-reviewed randomized controlled trial that demonstrated clinical utility over the standard of care when physicians used IDgenetix prior to prescribing a medication. The trial was conducted across 20 independent clinical sites within the United States specializing in psychiatry, internal medicine, obstetrics & gynecology, and family medicine. As of December 31, 2024, our IDgenetix test is supported by 19 peer-reviewed publications.

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Table of Contents

Pipeline Initiatives

We have significant expertise in developing proprietary algorithms, conducting clinical studies and using the necessary instrumentation required for efficiently developing our pipeline products. Due to the biological complexity of diseases, developing accurate products takes scientific diligence, stringent clinical protocols, machine learning expertise, proprietary algorithms and significant investments of time and capital. In addition, the underlying tissue samples and associated clinical outcomes data required to develop and validate these products are difficult to obtain.

In 2021, we announced the launch of our innovative pipeline initiative to develop a genomic test, or series of tests, aimed at predicting response to systemic therapy in patients with moderate to severe atopic dermatitis (“AD”), psoriasis and related inflammatory skin conditions. In the same year, we initiated a large, prospective, multi-center clinical study to develop and validate this pipeline test, formed a steering committee comprised of leading experts in the field and received Institutional Revenue Board (“IRB”) approval. On December 23, 2024, we announced that preliminary data from our ongoing prospective development and validation study for our pipeline test has shown potential to identify a subset of patients with AD who have increased likelihood to achieve a super response to targeted therapies, indicated by a 90% or greater reduction in Eczema Area and Severity Index score at three months. AD is among the most common inflammatory skin condition, and patient quality of life is severely impacted by this chronic disease. In the United States alone, there are approximately six million patients diagnosed annually with moderate-to-severe AD and approximately 760,000 of these patients seek systemic treatment. As of December 31, 2024, there were more than 39 active clinical study sites and over 1,100 patients enrolled in our inflammatory skin development and validation study. Assuming successful validation, we expect to launch this pipeline test by the end of 2025.

U.S. TAM is based on estimated patient population assuming average reimbursement rate among all payors.

We expect to continue pursuing pipeline initiatives for tests that