Castle Biosciences’ Abstracts at Digestive Disease Week (DDW) Annual Meeting Selected as “Posters of Distinction” by the American Gastroenterological Association (AGA) Institute Council

New data demonstrate the risk-stratification performance and potential of the TissueCypher® Barrett’s Esophagus test to guide risk-aligned patient care decisions

FRIENDSWOOD, Texas--()--Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, today announced that its three posters at the recent DDW Annual Meeting were honored as “Posters of Distinction” by the AGA Institute Council, ranking among the top 10% of the more than 3,100 abstracts showcased during the meeting.

“We are incredibly proud that all three of our posters presented at the recent DDW Annual Meeting received 'Poster of Distinction' honors,” said Robert Cook, Ph.D., senior vice president of research and development at Castle Biosciences. “We believe this signifies the value of our TissueCypher test in providing objective risk-stratification that can inform improved management decisions for patients with Barrett’s esophagus (BE).”

Following are highlights of Castle’s “Posters of Distinction” at DDW 2023. Full-text abstracts will be published in the May online supplement to Gastroenterology; the posters are available on the DDW ePosters site under Posters of Distinction category, Esophageal Diseases.

Poster # Tu1272: A Tissue Systems Pathology Test Objectively Risk-Stratifies Patients with Barrett’s Esophagus: Results from a Multicenter U.S. Clinical Experience
Presenter: Study Author, Michael Yodice, M.D., Geisinger Health

TissueCypher test results from 2,456 BE patients ordered by 273 physicians at 32 academic centers and 161 community centers between June 2016 and October 2022 were evaluated in the study. TissueCypher risk-stratified patients in each pathologic (non-dysplastic BE (NDBE), indefinite for dysplasia (IND) and low-grade dysplasia (LGD)) and clinicopathologic (females, males, short-segment BE and long-segment BE) subset. Intermediate-risk TissueCypher scores in NDBE patients predicted a five-year risk of progression to high-grade dysplasia (HGD)/esophageal adenocarcinoma (EAC) of 6.2%, which was similar to the progression risk of 4.8% in patients with LGD in this community-based cohort, as well as published estimates. High-risk TissueCypher scores in NDBE patients predicted a five-year progression risk of 9.9%, which is higher than published estimates of progression in expert pathologist confirmed LGD.

Overall, the study data indicate that TissueCypher’s objective risk-stratification has significant, independent clinical utility to improve management decisions for BE patients in surveillance. The test can increase the early detection of progressors with NDBE and can enable clinicians and patients to consider risk-aligned management options to improve patient health outcomes.

Poster # Tu1271: A Tissue Systems Pathology Test Enables Standardized, Risk-Aligned Management of Patients with Barrett’s Esophagus
Presenter: Senior Author, Jacques Bergman, M.D., Ph.D., Amsterdam University Medical Centers

The real-world pathology diagnoses, expert review diagnoses, TissueCypher test results and patient outcomes were collected for 699 patients from five completed clinical validation studies. Management decisions were then simulated using the real-world diagnoses with expert review of LGD, with or without guidance from TissueCypher test results.

In this simulation study in a cohort of 699 patients with known clinical outcomes, the TissueCypher test demonstrated significant clinical utility, particularly in patients with NDBE, enabling more progressors to be appropriately managed with endoscopic eradication therapy (EET) to prevent progression, or short interval surveillance, which are highly effective management strategies to improve BE patient health outcomes. In patients with NDBE, the percentage of progressors receiving appropriate management increased from zero, using standard of care (SOC) pathology review alone to guide patient management, to 57% when TissueCypher test results were used with the SOC to guide decisions (p<0.0001). Additionally, use of TissueCypher led to a 49% decrease in the undertreatment of patients who progressed to HGD/EAC (p<0.0001) without increasing the overtreatment of patients who did not progress to more advanced dysplasia.

Poster # Tu1270: A Tissue Systems Pathology Test has Significant Clinical Utility to Standardize Management Leading to Improved Health Outcomes for Barrett’s Esophagus Patients with Low-Grade Dysplasia
Presenter: Senior Author Jacques Bergman, M.D., Ph.D., Amsterdam University Medical Centers

In the patient simulation study performed in the screening cohort of a randomized controlled trial (n=154), the percentage of patients with 100% likelihood of receiving appropriate management per their known progression outcome increased from 9.1% with a pathologist diagnosis alone to 31.8% when TissueCypher test results were considered in conjunction with pathology; this further increased to 77.3% when TissueCypher test results were used alone. Overall, the study data showed that, compared to pathology alone, using TissueCypher test results to guide management decisions significantly increased the percentage of BE patients receiving appropriate management per their known outcome (p=0.0007), which supports use of the test to help standardize the management of BE patients to potentially improve their overall care and health outcomes.

About Digestive Disease Week® (DDW)

Digestive Disease Week® (DDW) is the largest international gathering of physicians, researchers and academics in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery. Jointly sponsored by the American Association for the Study of Liver Diseases (AASLD), the American Gastroenterological Association (AGA), the American Society for Gastrointestinal Endoscopy (ASGE) and the Society for Surgery of the Alimentary Tract (SSAT), DDW was held in-person and online from May 6-9, 2023. The meeting showcased more than 3,100 abstracts and hundreds of lectures on the latest advances in GI research, medicine and technology. More information can be found at www.ddw.org.

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). TissueCypher is indicated for use in patients with endoscopic biopsy confirmed BE that is graded non-dysplastic (ND), indefinite for dysplasia (IND) or low-grade dysplasia (LGD); its clinical performance has been supported by nine peer-reviewed publications of BE progressor patients with leading clinical centers around the world. The TissueCypher Barrett’s Esophagus Assay is a proprietary Laboratory Developed Test with its own unique CPT PLA code (0108U). Additionally, the test received Advanced Diagnostic Laboratory Test (ADLT) status from the Centers for Medicare & Medicaid Services (CMS) in March 2022 and was recognized by the American Gastroenterological Association (AGA) in their 2022 Clinical Practice Update as a tool that may be used to risk-stratify patients with NDBE.

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, Twitter and Instagram.

DecisionDx-Melanoma, DecisionDx-CMSeq, DecisionDx-SCC, MyPath Melanoma, DiffDx-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: the potential of TissueCypher test results to (i) guide risk-aligned patient care decisions; (ii) inform improved management decisions for patients with Barrett’s esophagus; (iii) increase the early detection of progressors with NDBE, and enable clinicians and patients to consider risk-aligned management options to improve patient health outcomes; and (iv) improve overall care and health outcomes. The words “believe,” “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 these studies, including with respect to the discussion of TissueCypher 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 Quarterly Report on Form 10-Q for the quarter ended March 31, 2023, 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.

Contacts

Investor Contact:
Camilla Zuckero
czuckero@castlebiosciences.com

Media Contact:
Allison Marshall
amarshall@castlebiosciences.com

Release Summary

Castle announced that its three posters at the recent DDW Annual Meeting were honored as “Posters of Distinction” by the AGA Institute Council.

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Contacts

Investor Contact:
Camilla Zuckero
czuckero@castlebiosciences.com

Media Contact:
Allison Marshall
amarshall@castlebiosciences.com