Castle Biosciences (CSTL) investor relations material

Business performance and financial highlights

• Achieved strong Q1 results with 16% YoY growth in DecisionDx-Melanoma and 58% YoY growth in TissueCypher test volumes.

• Raised 2026 revenue guidance to $345–$355 million, with Q1 revenue just under $84 million and $262 million in cash.

• Adjusted gross margin reached 75.6%, with negative adjusted EBITDA of $5.1 million and $22 million in operating cash flow.

• DecisionDx-SCC volumes declined due to loss of Medicare coverage, but demand exceeded forecasts, reflecting clinical value.

• Commercial focus remains on dermatology and gastroenterology, with ongoing R&D and pipeline expansion.

Product innovation and clinical impact

• DecisionDx-Melanoma and DecisionDx-SCC provide risk stratification and therapy selection, with SCC test guiding adjuvant radiation therapy.

• TissueCypher test for Barrett's esophagus enables risk stratification, reducing unnecessary endoscopies and increasing appropriate interventions.

• AdvanceAD-Tx, launched late 2025, uses non-biopsy scraping and gene profiling to guide systemic therapy selection in atopic dermatitis.

• New pipeline includes collaboration with SciBase for MRD-like monitoring in atopic dermatitis using electrical impedance spectroscopy.

• Product portfolio expansion aims to leverage core franchises and drive mid- to long-term value.

Market opportunity and reimbursement landscape

• Estimated U.S. TAM for TissueCypher is $1 billion, with 400 clinicians using the test as of Q1 2026.

• Atopic dermatitis market includes 10 million moderate-to-severe patients, with high therapy switching rates highlighting unmet need.

• DecisionDx-SCC remains available despite reimbursement challenges, supported by low production costs and overlapping clinician base.

• Growing state biomarker laws are expected to improve coverage and payment for validated tests, benefiting the broader market.

• Increased test optionality and market noise seen as positive for awareness and legislative progress, though not expediting payer decisions.