8-K: Castle Biosciences Raises 2025 Revenue Guidance Amidst Q3 Test Volume Growth

Castle Biosciences reported mixed third-quarter 2025 financial results, including a revenue decline, but raised its full-year 2025 revenue guidance and launched a new atopic dermatitis test.

Summary

• Third quarter 2025 revenue was $83.0 million, a decrease from $85.8 million in Q3 2024.
• Total test reports delivered in Q3 2025 increased to 26,841 from 26,010 in Q3 2024.
• Core revenue drivers (DecisionDx-Melanoma and TissueCypher) test reports increased 36% over Q3 2024, with each surpassing 10,000 reports for the first time in a single quarter.
• Non-dermatologic revenue increased by 67% over Q3 2024.
• Net loss for Q3 2025 was $0.5 million, compared to net income of $2.3 million in Q3 2024.
• Adjusted EBITDA for Q3 2025 was $9.2 million, down from $21.6 million in Q3 2024.
• Full-year 2025 revenue guidance was raised to $327-335 million from the previous range of $310-320 million.
• Launched AdvanceAD-Tx, a new gene expression profile (GEP) test for moderate-to-severe atopic dermatitis, on November 3, 2025.

Sentiment

Score: 7

Explanation: The sentiment is moderately positive. While Q3 2025 financial results showed a year-over-year decline in revenue and a shift to net loss and lower EBITDA, the company raised its full-year revenue guidance, indicating confidence in future performance. Strong growth in core test volumes and the launch of a new product in a large market are significant positive drivers, outweighing the Q3 financial dips which were partly attributed to specific coverage decisions and product discontinuation.

Positives

• Full-year 2025 revenue guidance was raised to $327-335 million, up from $310-320 million, indicating strong future expectations.
• Total test reports for core revenue drivers (DecisionDx-Melanoma and TissueCypher) increased by 36% over Q3 2024.
• Non-dermatologic revenue saw a significant 67% increase over Q3 2024.
• DecisionDx-Melanoma test reports increased to 10,459 in Q3 2025 from 9,367 in Q3 2024.
• TissueCypher Barretts Esophagus test reports significantly increased to 10,609 in Q3 2025 from 6,073 in Q3 2024.
• Launched AdvanceAD-Tx, an innovative, first-in-class test addressing a significant unmet need in clinical dermatology with an estimated $33 billion U.S. total addressable market.
• Strong cash, cash equivalents, and marketable investment securities totaling $287.5 million as of September 30, 2025.
• New data presented supporting DecisionDx-Melanoma's ability to stratify risk across histological subtypes and improve patient survival.
• Two new studies published supporting DecisionDx-SCC's clinical utility in predicting local recurrence, metastasis, and benefit from adjuvant radiation therapy.
• New data demonstrated TissueCypher Barretts Esophagus's personalized risk stratification for non-dysplastic Barrett's esophagus patients.
• Founder, President, and CEO Derek Maetzold was named CEO of the Year by The CEO Magazine.
• Recognized as a Greater Pittsburgh Top Workplace and included in Newsweek's inaugural 2025 Americas Greatest Companies list.

Negatives

• Third quarter 2025 revenue decreased to $83.0 million from $85.8 million in Q3 2024.
• Gross margin decreased to 75% in Q3 2025 from 79% in Q3 2024.
• Adjusted Gross Margin decreased to 77% in Q3 2025 from 82% in Q3 2024.
• Net cash provided by operations decreased to $22.6 million in Q3 2025 from $23.3 million in Q3 2024.
• Shifted to a net loss of $0.5 million in Q3 2025, compared to net income of $2.3 million in Q3 2024.
• Adjusted EBITDA significantly decreased to $9.2 million in Q3 2025 from $21.6 million in Q3 2024.
• The Novitas local coverage determination (LCD) for DecisionDx-SCC, effective April 24, 2025, included it as noncovered, negatively affecting Q3 2025 revenue and test report volume.
• Discontinuation of the IDgenetix test offering in May 2025 impacted Q3 2025 revenue and test report volume.

Risks

• Uncertainty regarding reimbursement for products and subsequent coverage decisions, including the Novitas LCD for DecisionDx-SCC.
• Accuracy of estimated total addressable markets for products and product candidates.
• Expenses, capital requirements, and potential needs for additional financing.
• Anticipated cost, timing, and success of product candidates.
• Ability to successfully integrate new businesses, assets, products, or technologies acquired through acquisitions.
• Effects of macroeconomic events and conditions, including inflation, monetary supply shifts, labor shortages, liquidity concerns at financial institutions, recession risks, supply chain disruptions, tariffs, contagious diseases, and geopolitical events.
• Possibility that subsequent study or trial results and findings may contradict earlier results or not support the benefits discussed.
• Planned installation of additional equipment and technology infrastructures and implementation of process efficiencies may not increase the future scalability of the TissueCypher Test as anticipated.
• Actual application of tests may not provide the anticipated benefits to patients.
• Newer gastroenterology and mental health franchises may not contribute to the achievement of long-term financial targets as anticipated.

Future Outlook

The company anticipates generating between $327-335 million in total revenue in 2025, an increase from previous guidance. It expects continued top-line performance and growth of test volumes, with core dermatologic and gastrointestinal testing franchises driving momentum. The launch of AdvanceAD-Tx is expected to provide substantial added value to clinicians and patients. The company aims to achieve operating cash flow positivity by the end of 2025 and maintain a strong balance sheet with disciplined capital allocation.

Management Comments

• "We delivered a strong third quarter, generating $83 million in revenue and 26,841 in total test report volume. These strong results are a testament to the workforce culture we have built at Castle and our unwavering commitment to improving patient care."
• "Our momentum this quarter reflects the strength of our core dermatologic and gastrointestinal testing franchises, with DecisionDx-Melanoma and TissueCypher each surpassing 10,000 test reports for the first time in a single quarter, significant milestones that underscore the expanding adoption of our core tests."
• "Based on our strong execution, we are raising our full-year 2025 total revenue guidance to $327-335 million from the previously provided range of $310-320 million."
• "Additionally, with the launch of AdvanceAD-Tx, our new test designed to guide systemic treatment decision making in patients with moderate-to-severe atopic dermatitis, we are thrilled to provide an additional innovative, first-in-class, proprietary test addressing a significant unmet need in clinical dermatology."

Industry Context

Operating in the specialized diagnostics sector, the company's focus on dermatologic and gastroenterological diseases aligns with a broader industry trend towards personalized medicine and precision diagnostics. The launch of AdvanceAD-Tx for atopic dermatitis positions the company in a large and growing market, indicating strategic expansion into areas with significant unmet clinical needs. The impact of the Novitas LCD on DecisionDx-SCC highlights the ongoing challenges and importance of reimbursement and coverage decisions in the diagnostics industry, where regulatory hurdles can significantly affect product adoption and revenue streams. The company's emphasis on robust clinical evidence is crucial for driving adoption and securing favorable reimbursement in a competitive landscape.

Comparison to Industry Standards

• No specific comparable companies, projects, or results are detailed in the filing to provide a direct assessment against global benchmarks.

Stakeholder Impact

• Shareholders: Mixed financial performance in Q3 2025 (revenue decline, net loss) but positive outlook with raised full-year guidance and strong core test volume growth. New product launch offers future growth potential.
• Patients: Introduction of AdvanceAD-Tx and expanded clinical utility for existing tests (DecisionDx-Melanoma, DecisionDx-SCC, TissueCypher) aim to improve diagnostic accuracy and guide treatment decisions, potentially leading to better health outcomes.
• Employees: Recognition as a 'Greater Pittsburgh Top Workplace' and inclusion in 'Americas Greatest Companies' list suggests a positive work environment and strong corporate culture.
• Clinicians: New and enhanced diagnostic tools provide more comprehensive and personalized information to support tailored patient management and treatment planning.

Next Steps

• Hold a conference call and webcast on November 3, 2025, at 4:30 p.m. ET to discuss Q3 2025 results and provide a corporate update.
• Anticipate phased, expanded availability of AdvanceAD-Tx through 2026.
• Goal to achieve operating cash flow positivity by the end of 2025.
• Continue to build robust clinical evidence for existing and pipeline tests.
• Further penetrate target markets to drive test adoption by clinicians and payers.

Key Dates

Recommendation

The company presents a mixed financial picture for Q3 2025, with a year-over-year decline in revenue, a shift to net loss, and a significant drop in Adjusted EBITDA. These declines are partly attributed to specific reimbursement challenges and product discontinuation. However, strong growth in core test volumes, the launch of a new product (AdvanceAD-Tx) targeting a substantial market, and a raised full-year revenue guidance signal management's confidence and operational strength. The strong cash position provides stability. Investors should monitor the impact of new product adoption and ongoing reimbursement dynamics on future profitability before making a more aggressive move.

Keywords

Diagnostics, Gene Expression Profile, Dermatology, Gastroenterology, Atopic Dermatitis, Melanoma, Squamous Cell Carcinoma, Barrett's Esophagus, Q3 2025 Earnings, Revenue Guidance, AdvanceAD-Tx, DecisionDx-Melanoma, TissueCypher