Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from _________ to _________ Commission File Number: 001-38984 CASTLE BIOSCIENCES, INC. (Exact name of registrant as specified in its charter) (St ...

Exhibit 99.1 Castle Biosciences Reports First Quarter 2025 Results Q1 2025 revenue increased 21% over Q1 2024 to $88 million ® ® Q1 2025 total test reports for our core revenue drivers (DecisionDx -Melanoma, DecisionDx -SCC, TissueCypher ) increased 33% over Q1 2024 ® Raising full-year 2025 revenue guidance to $287-297 million from $280-295 million Conference call and webcast today at 4:30 p.m. ET FRIENDSWOOD, Texas - May 5, 2025--Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through i ...

Core Insights - Castle Biosciences, Inc. reported a 21% increase in Q1 2025 revenue to $88 million compared to Q1 2024 [1] - The company raised its full-year 2025 revenue guidance to $287-297 million from the previous range of $280-295 million [1][6] - The total test reports for core revenue drivers increased by 33% over Q1 2024 [1] Financial Performance - Revenues for Q1 2025 were $88 million, up from $73 million in Q1 2024, representing a 21% increase [4] - Adjusted revenues, excluding prior period adjustments, were $87.2 million, a 22% increase from $71.3 million in the same period last year [4] - The gross margin was 49%, while the adjusted gross margin remained at 81% [4] - The net loss for Q1 2025 was $25.8 million, compared to a net loss of $2.5 million in Q1 2024 [4][8] Operational Highlights - The company delivered 24,402 total test reports in Q1 2025, a 17% increase from 20,888 in Q1 2024 [4] - DecisionDx-Melanoma surpassed 200,000 test orders since its launch, indicating strong demand and clinical value [3][9] - The company decided to discontinue the IDgenetix test offering effective May 2025 [4][12] Cash Position - As of March 31, 2025, the company's cash, cash equivalents, and marketable investment securities totaled $275.2 million [5] Future Outlook - The company anticipates total revenue in 2025 to be between $287-297 million, reflecting confidence in continued growth [6] - Castle Biosciences is focused on expanding its proprietary test portfolio and enhancing patient outcomes [4][22]

Core Insights - Castle Biosciences has signed a definitive agreement to acquire Capsulomics, Inc., also known as Previse, which focuses on gastrointestinal health, particularly chronic acid reflux diseases and esophageal cancer [2][3] - The acquisition aims to enhance Castle's existing gastroenterology franchise by integrating Previse's methylation technology and other developmental technologies, thereby expanding its testing options [3][4] - The transaction is expected to close in the coming weeks, pending customary closing conditions [3] Company Overview - Castle Biosciences is a diagnostics company listed on Nasdaq (CSTL) that develops innovative tests to guide patient care and improve health outcomes [5] - The company's current portfolio includes tests for skin cancers, Barrett's esophagus, mental health conditions, and uveal melanoma, with ongoing research in other high clinical need areas [6] Previse Overview - Previse, established in 2018, specializes in gastrointestinal health and aims to improve patient outcomes through early detection and prevention of diseases like esophageal cancer [4] - The company utilizes advanced biomarker technology developed at Johns Hopkins University, which is exclusively licensed to Previse, to support its mission [4]

Core Insights - Castle Biosciences, Inc. is presenting new data on its TissueCypher Barrett's Esophagus test at the Digestive Disease Week® (DDW 2025) Annual Meeting, emphasizing its role in improving risk stratification and management of Barrett's esophagus patients [1][2][9] Company Overview - Castle Biosciences is a diagnostics company focused on innovative tests that guide patient care, with a portfolio that includes tests for skin cancers, Barrett's esophagus, and mental health conditions [10][11] - The TissueCypher Barrett's Esophagus test is designed to predict the future development of high-grade dysplasia and/or esophageal cancer in patients with Barrett's esophagus [9] Event Highlights - The company will showcase two posters at DDW 2025, including findings on the detection of missed neoplasia and risk stratification for Barrett's esophagus patients [3][2] - A product theater titled "The Time is Now: A Clinical Practice Model to Help Prevent Progression from Barrett's to EAC" will be hosted by an expert physician panel [1][6] Educational Collaborations - Castle is collaborating with the American Society for Gastrointestinal Endoscopy (ASGE) and other GI experts to conduct educational sessions on the use of TissueCypher [1][2]

Core Insights - Castle Biosciences, Inc. announced that its DecisionDx-Melanoma test significantly outperforms traditional methods in identifying low-risk melanoma patients who may avoid sentinel lymph node biopsy (SLNB) surgery, with a sentinel lymph node positivity rate of 2.8%, well below the NCCN's 5% threshold [1][2][3] Company Overview - Castle Biosciences is a diagnostics company focused on innovative tests that enhance patient care, with a portfolio that includes tests for skin cancers and other conditions [6][8] - The DecisionDx-Melanoma test has been ordered over 200,000 times for patients diagnosed with cutaneous melanoma, demonstrating its widespread adoption and clinical relevance [5] Study Findings - The study published in Cancer Diagnosis & Prognosis indicates that DecisionDx-Melanoma provides better risk stratification compared to the American Joint Committee on Cancer (AJCC) staging and the CP-GEP test, confirming its clinical utility [2][3] - Patients identified as low risk by CP-GEP had a sentinel lymph node positivity rate of 6.2%, while those identified by DecisionDx-Melanoma had a significantly lower rate of 2.8%, highlighting the latter's superior accuracy [3] Clinical Implications - The findings support the use of DecisionDx-Melanoma in clinical decision-making, allowing clinicians to confidently recommend forgoing SLNB for patients with low-risk results, thereby improving patient outcomes and reducing unnecessary procedures [4][5] - The test integrates tumor biology with clinical factors, providing personalized risk assessments for sentinel lymph node positivity and melanoma recurrence [5]

Core Insights - Castle Biosciences has achieved a significant milestone by surpassing 200,000 orders for its DecisionDx-Melanoma test, which aids in providing personalized insights for melanoma treatment decisions [2][7] - The DecisionDx-Melanoma test is a 31-gene expression profile test designed to improve risk-aligned management decisions for patients with stage I-III cutaneous melanoma [2][6] - The test integrates genetic information from tumor biology with traditional clinical features to stratify patient risk and predict recurrence and metastasis [4][6] Company Overview - Castle Biosciences, Inc. (Nasdaq: CSTL) focuses on improving health through innovative diagnostic tests that guide patient care [2][8] - The company aims to transform disease management by prioritizing the needs of patients, clinicians, employees, and investors [8] - Castle's portfolio includes tests for various conditions, including skin cancers and mental health, with ongoing research for additional tests in high clinical need areas [9] Clinical Impact - The clinical value of DecisionDx-Melanoma is supported by over 50 peer-reviewed publications and has been studied in more than 10,000 patient samples, demonstrating its association with improved patient survival [4][7] - The test provides actionable results that help clinicians make informed treatment decisions, ultimately improving patient outcomes [3][4]

FRIENDSWOOD, Texas, April 25, 2025 (GLOBE NEWSWIRE) -- Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, will share new research intended to improve the care of patients with cutaneous and uveal melanoma (CM and UM, respectively) via poster presentations at the American Association for Cancer Research® (AACR) Annual Meeting 2025, being held April 25-30 in Chicago. "At Castle Biosciences, our commitment to advancing care for melanoma patient ...

FRIENDSWOOD, Texas, April 14, 2025 (GLOBE NEWSWIRE) -- Castle Biosciences, Inc. (NASDAQ:CSTL), a company improving health through innovative tests that guide patient care, today announced that it will release its financial results for the first quarter ended March 31, 2025, after the close of market on Monday, May 5, 2025. Company management will host a conference call and webcast to discuss its financial results at 4:30 p.m. Eastern time on the same day. Conference Call and Webcast DetailsA live webcast of ...

Core Viewpoint - Castle Biosciences is actively promoting awareness and education regarding esophageal cancer during Esophageal Cancer Awareness Month, collaborating with various organizations to enhance prevention and early detection efforts [1][2][3]. Company Initiatives - Castle Biosciences is collaborating with the Esophageal Cancer Action Network (ECAN), the American Foregut Society (AFS), and The Gut Doctor Podcast to support educational programs and initiatives throughout April [1][3]. - The company is utilizing a digital media campaign and awareness kits to disseminate information about esophageal cancer, emphasizing its preventability and the importance of early detection [3][4]. - Castle's TissueCypher® test is designed to assess the risk of Barrett's esophagus patients progressing to esophageal cancer, which is crucial for timely intervention [2][11]. Industry Context - Esophageal cancer has a low five-year survival rate of approximately 20%, often diagnosed at advanced stages, highlighting the need for increased awareness and early detection [2][4]. - The incidence of esophageal cancer is rising, particularly among young individuals, making awareness and education critical in combating this disease [4][8]. - The collaboration with advocacy groups aims to increase federal funding for esophageal cancer research, which has seen an increase of over $20 million in the past four years [8].