Silence Therapeutics Plc: Q3 2025 10-Q Summary
Business Context and Reporting Period
This Quarterly Report on Form 10-Q covers the period ended September 30, 2025. Silence Therapeutics Plc is a biotechnology company focused on discovering and developing RNA therapeutics (siRNA) for cardiovascular, hematology, and rare diseases. The company operates as a single reportable segment. Effective January 1, 2025, the company transitioned from a foreign private issuer to a domestic filer, changing its reporting currency from British Pounds (GBP) to U.S. Dollars (USD) and adopting U.S. GAAP retrospectively.
Key Financial Metrics
| Metric | Q3 2025 (3 Months) | Q3 2024 (3 Months) | YTD 2025 (9 Months) | YTD 2024 (9 Months) |
|---|---|---|---|---|
| Revenue | $0.2 million | $1.5 million | $0.5 million | $18.0 million |
| Net Loss | $(21.0) million | $(35.5) million | $(76.8) million | $(57.6) million |
| Operating Loss | $(26.2) million | $(30.0) million | $(78.6) million | $(59.0) million |
| R&D Expenses | $(20.5) million | $(20.2) million | $(59.0) million | $(45.8) million |
| Cash & Equivalents | $82.0 million (as of Sept 30, 2025) | |||
| Total Liquidity | $102.2 million (Cash + Short-term investments) | |||
| Operating Cash Flow | $(45.0) million (YTD 2025) |
Material Changes vs. Prior Period
- Revenue Decline: Revenue decreased significantly year-over-year. For the nine months ended September 30, 2025, revenue dropped $17.4 million compared to the prior year. This was primarily due to the absence of a $10.0 million milestone payment from the AstraZeneca collaboration recognized in the same period of 2024. Additionally, revenue from the Hansoh and Mallinckrodt collaborations ceased as those agreements concluded in late 2024.
- Net Loss Increase: The net loss for the nine months ended September 30, 2025, increased by $19.2 million compared to the prior year. This increase was driven by higher R&D expenses ($13.2 million increase) related to the advancement of proprietary programs (divesiran Phase 2 and zerlasiran Phase 3 readiness), partially offset by a significant foreign currency gain of $8.4 million (compared to a loss of $11.3 million in the prior year) and a reduction in G&A expenses.
- Restructuring: The company incurred $1.3 million in restructuring charges during the first half of 2025 associated with a workforce reduction, which did not occur in the comparable prior period.
- Liquidity Position: Cash and cash equivalents decreased by approximately $39.3 million during the nine-month period, reflecting operating outflows and the lack of significant financing activities in 2025 compared to the $120 million private placement in early 2024.
Guidance, Outlook, and Risks
- Outlook: Management believes current cash, cash equivalents, and short-term investments ($102.2 million) are sufficient to fund operations into 2028, assuming the receipt of anticipated milestone payments totaling $20.0 million from existing collaborations over the next three years.
- Clinical Progress:
- Divesiran (SLN124): The SANRECO Phase 2 trial for polycythemia vera (PV) is fully enrolled. Initial topline results are anticipated in Q3 2026.
- Zerlasiran (SLN360): The company has completed Phase 3 readiness activities and is seeking a third-party partner for Phase 3 development and commercialization.
- Risks and Contingencies:
- Funding Dependency: The company has incurred recurring losses since inception and will require additional capital to fund future operations. Failure to secure funding could force delays or elimination of R&D programs.
- Regulatory and Legislative: Risks include potential changes in healthcare legislation (e.g., the "One Big Beautiful Bill Act" signed July 2025), drug pricing reforms, and evolving data privacy laws (GDPR, CCPA) which could impact operations and costs.
- Collaboration Milestones: Future revenue is contingent on achieving specific development and regulatory milestones with partners like AstraZeneca, which are not guaranteed.
Investor Verification Checklist
- Cash Runway: Verify the sufficiency of the $102.2 million liquidity position against the projected burn rate, specifically noting the reliance on future milestone payments to extend the runway to 2028.
- Revenue Recognition: Review the accounting treatment of collaboration revenue (AstraZeneca) under ASC 606, specifically the cost-to-cost method used to recognize upfront and milestone payments over time.
- R&D Spend Efficiency: Assess the $13.2 million increase in R&D expenses against tangible clinical milestones achieved (e.g., Phase 2 enrollment completion for divesiran).
- Partnership Status: Confirm the status of the search for a Phase 3 partner for zerlasiran and the likelihood of receiving the anticipated $20 million in future milestones.
- Regulatory Exposure: Evaluate the potential financial impact of new U.S. healthcare legislation and data privacy regulations on future commercialization and operational costs.