• Data shared via a poster presentation at the recent American Foregut Society (AFS) Annual Meeting

FRIENDSWOOD, Texas / Oct 02, 2023 / Business Wire / Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced new data demonstrating the significant clinical utility of its TissueCypher® Barrett’s Esophagus test in guiding risk-aligned upstaging of care for patients with non-dysplastic Barrett’s esophagus (NDBE) at a higher risk of progression to high-grade dysplasia (HGD) or esophageal adenocarcinoma (EAC) than indicated by their clinicopathologic risk factors.

The data was presented in a poster at the recent American Foregut Society (AFS) Annual Meeting. The poster, titled “A Tissue Systems Pathology Test Enables Risk-Aligned Management of Patients with Non-Dysplastic Barrett’s Esophagus: Case Reports from a Gastrointestinal Surgery Center,” can be viewed here.

"In the management of BE, there are several therapeutic strategies to help prevent the development of esophageal cancer,” said Daniel Tseng, M.D., F.A.C.S., surgeon at Northwest Minimally Invasive Surgery Center in Portland, Oregon, and lead author of the study. “These options include endoscopic eradication therapies (EET) such as radiofrequency ablation (RFA) or cryoablation, as well as anti-reflux surgery that can stop chronic injury to the esophagus.

“The challenge arises in predicting which patients in the large pool of those with NDBE are most likely to progress and could thus benefit from these treatments early, when they are most effective. These case studies support the use of TissueCypher to potentially identify which NDBE patients are at a higher risk of disease progression and should be managed accordingly.”

The overall population of patients with NDBE are considered to be at low risk for progression based on their clinicopathologic risk factors. However, the high incidence of NDBE indicates that at least half of the patients who progress to HGD/EAC annually are diagnosed as NDBE and can be missed by current clinicopathologic-based risk stratification and therefore, undertreated. The case study reinforced the ability of TissueCypher to identify NDBE patients at high/intermediate risk for progression to HGD/EAC. The patients in the case study had predicted 5-year risk of progression to HGD/EAC that was similar (range 6-14%) to the published estimates of progression in patients with confirmed low-grade dysplasia (LGD) (8.5%), a pathologic diagnosis associated with higher progression risk for which guidelines recommend EET, such as RFA. Identification of NDBE patients with similar progression risk to LGD enables physicians and their patients to consider risk-aligned upstaging of care to prevent development of EAC and improve their overall health outcomes.

About TissueCypher^® Barrett’s Esophagus Test

The TissueCypher Barrett’s Esophagus test is Castle’s precision medicine test designed to predict future development of high-grade dysplasia (HGD) and/or esophageal cancer in patients with Barrett’s esophagus (BE). The TissueCypher Barrett’s Esophagus test is indicated for use in patients with endoscopic biopsy confirmed BE that is graded non-dysplastic (NDBE), indefinite for dysplasia (IND) or low-grade dysplasia (LGD); its clinical performance has been supported by 12 peer-reviewed publications of BE progressor patients with leading clinical centers around the world. The test received Advanced Diagnostic Laboratory Test (ADLT) status from the Centers for Medicare & Medicaid Services (CMS) in March 2022.

About Castle Biosciences

Castle Biosciences (Nasdaq: CSTL) is a leading diagnostics company improving health through innovative tests that guide patient care. The Company aims to transform disease management by keeping people first: patients, clinicians, employees and investors.

Castle’s current portfolio consists of tests for skin cancers, uveal melanoma, Barrett’s esophagus and mental health conditions. Additionally, the Company has active research and development programs for tests in other diseases with high clinical need, including its test in development to predict systemic therapy response in patients with moderate-to-severe psoriasis, atopic dermatitis and related conditions. To learn more, please visit www.CastleBiosciences.com and connect with us on LinkedIn, Facebook, X and Instagram.

DecisionDx-Melanoma, DecisionDx-CMSeq, DecisionDx-SCC, MyPath Melanoma, DecisionDx-UM, DecisionDx-PRAME, DecisionDx-UMSeq, TissueCypher and IDgenetix are trademarks of Castle Biosciences, Inc.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the “safe harbor” created by those sections. These forward-looking statements include, but are not limited to, statements concerning: TissueCypher’s potential to identify which NDBE patients are at a higher risk of disease progression and should be managed accordingly. The words “can,” “potential” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements that we make. These forward-looking statements involve risks and uncertainties that could cause our actual results to differ materially from those in the forward-looking statements, including, without limitation: subsequent study or trial results and findings may contradict earlier study or trial results and findings or may not support the results shown in this study, including with respect to the discussion of the TissueCypher® Barrett’s Esophagus test in this press release; actual application of our tests may not provide the aforementioned benefits to patients; and the risks set forth under the heading “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2022, and in our other filings with the SEC. The forward-looking statements are applicable only as of the date on which they are made, and we do not assume any obligation to update any forward-looking statements, except as may be required by law.