Business Context and Reporting Period
Company: Silence Therapeutics plc (Nasdaq: SLN)
Filing Type: Form 10-K (Annual Report)
Reporting Period: Fiscal year ended December 31, 2025
Business Overview: Silence Therapeutics is a clinical-stage biotechnology company developing siRNA therapeutics using its proprietary mRNAi GOLD platform. The company focuses on rare and common diseases, including polycythemia vera (PV), cardiovascular disease, and obesity. It has no approved products and generates revenue primarily through collaboration agreements.
Key Financial Metrics
| Metric | 2025 | 2024 |
|---|---|---|
| Revenue | $0.6 million | $43.3 million |
| Net Loss | $(88.6) million | $(45.3) million |
| Operating Loss | $(91.1) million | $(63.3) million |
| Research & Development Costs | $(67.8) million | $(67.9) million |
| General & Administrative Expenses | $(22.3) million | $(26.9) million |
| Cash, Cash Equivalents & Short-term Investments | $85.1 million | $147.3 million |
| Accumulated Deficit | $(562.6) million | $(474.0) million |
| Net Cash Used in Operating Activities | $(62.3) million | $(67.6) million |
Note: The company reported a foreign currency loss of $8.5 million in 2025 compared to a gain of $0.6 million in 2024. Benefit from R&D tax credits was $7.5 million in 2025 versus $13.7 million in 2024.
Material Changes vs. Prior Period
- Revenue Decline: Revenue dropped 99% to $0.6 million. This was primarily due to the conclusion of the Hansoh collaboration in December 2024, which resulted in a $24.6 million revenue recognition in 2024 that did not recur. Additionally, no milestone payments were achieved under the AstraZeneca collaboration in 2025, compared to $10.0 million in 2024.
- Increased Net Loss: Net loss nearly doubled to $88.6 million, driven by a significant foreign currency loss ($8.5 million) and a reduction in R&D tax credit benefits due to changes in the U.K. tax regime.
- Collaboration Updates:
- Hansoh: Collaboration concluded in December 2024; Silence retained global rights to all three targets.
- AstraZeneca: Notified Silence in March 2026 that it would not pursue further development of SLN312 (ANGPTL3) beyond Phase 1. Silence will regain full global rights to this asset.
- Liquidity: Cash and short-term investments decreased by approximately $62 million year-over-year, largely due to operating outflows and net investing outflows related to the purchase of U.S. Treasury bills.
Guidance, Outlook, and Risks
Outlook and Milestones:
- Divesiran (SLN124): Phase 2 SANRECO trial for polycythemia vera is fully enrolled. Topline results are anticipated in Q3 2026 (accelerated from prior guidance of H2 2026).
- Zerlasiran (SLN360): Phase 3 ready for cardiovascular disease; seeking a third-party partner for development and commercialization.
- SLN312: Silence is evaluating plans for further clinical development after regaining rights from AstraZeneca.
- Discovery Pipeline: Anticipates additional preclinical data for SLN365 (cholesterol) and SLN098 (obesity) in Q2 2026.
Liquidity Position: Management believes current cash resources ($85.1 million) are sufficient to fund operations into 2028. However, the company expects to continue incurring significant losses and will require additional capital to advance clinical programs and commercialize products.
Key Risks:
- Going Concern: History of net losses and no product revenue; future funding is not guaranteed.
- Regulatory & Clinical: Uncertainty regarding clinical trial outcomes and regulatory approvals for siRNA therapeutics.
- Collaboration Dependence: Reliance on partners for funding and development; recent termination of AstraZeneca's development of SLN312 increases internal resource requirements.
- Foreign Exchange: Significant exposure to GBP/USD fluctuations, resulting in substantial non-cash losses in 2025.
Investor Verification Checklist
- Cash Runway: Verify the sufficiency of the $85.1 million cash balance to fund operations through 2028, considering the loss of potential milestone revenue from AstraZeneca and Hansoh.
- SLN312 Strategy: Confirm the specific plans and capital requirements for Silence to independently develop SLN312 after regaining rights from AstraZeneca.
- Partnership for Zerlasiran: Monitor progress in securing a third-party partner for the Phase 3 development of Zerlasiran, which is critical for commercialization.
- Foreign Exchange Hedging: Assess the company's strategy to mitigate future foreign currency losses given the significant impact in 2025.
- U.K. Tax Credit Eligibility: Verify continued qualification for U.K. R&D tax credits under the new "R&D-intensive" SME regime, which impacts cash flow.