Empowering people, informing care decisions August 2025 ©2025 Castle Biosciences 1 Disclaimers Forward-Looking Statements This presentation 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: our positioning for continued growth ...

Summary of Castle Biosciences Conference Call Company Overview - Castle Biosciences focuses on improving patient health through innovative diagnostic test services, either developed internally or acquired [2][6] - The company aims to impact the patient journey through diagnostic support, risk stratification, and therapy selection [3][4] Key Products and Services - **MyPath Melanoma**: Aids dermatopathologists in determining if a melanoma biopsy is positive [3] - **DecisionDx SCC**: A test for high-risk squamous cell carcinoma patients, predicting responsiveness to radiation therapy [4][28] - **DecisionDx Melanoma**: Developed to answer clinical questions regarding melanoma progression and recurrence [7][16] - **TissueCipher**: For patients with Barrett's esophagus, identifying those at risk of progression to esophageal adenocarcinoma [5][11] Clinical Evidence and Impact - The **DECIDE study** showed that patients who avoided sentinel lymph node biopsy due to low-risk results had 100% recurrence-free survival at two years [8] - The use of DecisionDx tests led to a **29% improvement** in three-year melanoma-specific survival compared to matched patients not tested [18] - The DecisionDx SCC test demonstrated a **50% reduction** in metastasis rates for patients receiving adjuvant radiation therapy [29] Financial Performance - The company reported a strong balance sheet with **$275 million** in cash at the end of Q1 2025 [32][40] - Adjusted gross margins maintained at approximately **80-81%** over the last five quarters [37] - Operating cash flow showed a trend of growth, with **$23 million** in operating cash flow in the last three quarters of the previous year [38] Strategic Goals - Continue to drive robust test volume growth and maintain industry-leading gross margins [31][32] - Focus on optimizing commercialization investments, particularly in dermatology and gastroenterology [40][42] - Explore potential acquisitions to enhance value in existing markets [43][44] Market Dynamics - Seasonal trends affect revenue, with expectations of increased melanoma detection in warmer months [33][34] - The decision to discontinue the iGenics test was made due to reimbursement challenges, impacting overall test volume [35][36] Conclusion - Castle Biosciences is positioned for growth with a strong product pipeline and strategic focus on enhancing patient care through advanced diagnostic testing. The company aims to maintain financial stability while expanding its market presence in dermatology and gastroenterology.