Castle Biosciences (CSTL) investor relations material

Executive summary

• Achieved strong Q4 and full year 2025 results, with $87M in Q4 revenue and $344.2M for the year, driven by core revenue drivers and disciplined execution.

• Core test volumes (DecisionDx-Melanoma, TissueCypher) grew 37% year-over-year, with TissueCypher up 86% and DecisionDx-Melanoma up 9%.

• Expanded commercial teams, completed the Previse acquisition, launched AdvanceAD-Tx, and entered a collaboration with SciBase.

• Strong balance sheet with $299.5M in cash, equivalents, and marketable securities at year-end.

• Limited access launch of AdvanceAD-Tx expanded the addressable market in dermatology.

Financial highlights

• Full year 2025 revenue was $344.2M, exceeding guidance; Q4 revenue was $87M.

• Gross margin for Q4 was 76.3% (vs. 76.2% prior year); full year gross margin was 69.2% (vs. 78.5% in 2024), impacted by loss of DecisionDx-SCC revenue and a $20.1M one-time amortization expense.

• Adjusted gross margin for 2025 was 79.8% (vs. 82% in 2024); adjusted EBITDA was $44M (vs. $75M in 2024).

• Net loss for 2025 was $24.2M (vs. net income of $18.2M in 2024); diluted loss per share was $0.83.

• Free cash flow for 2025 was $28.3M; cash, equivalents, and marketable securities totaled $299.5M at year-end.

Outlook and guidance

• 2026 revenue guidance is $340M–$350M, reflecting mid to high teens growth (excluding DecisionDx-SCC and IDgenetix).

• Continued growth expected in core dermatologic and GI franchises, with immaterial revenue from AdvanceAD-Tx and none from DecisionDx-SCC.

• Operating expenses expected to increase moderately in 2026 to support growth initiatives.

• AdvanceAD-Tx expected to contribute materially to revenue in 2027 or 2028.

• Continued focus on core test adoption, pipeline development, and leveraging a strong balance sheet.