Welcome to our dedicated page for Silence Therapeutics plc SEC filings (Ticker: SLN), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Silence Therapeutics plc filings document a foreign biotechnology issuer whose American Depositary Shares trade on Nasdaq under SLN, with each ADS representing three ordinary shares. The record includes 8-K reports furnishing quarterly and annual financial results, business highlights, Regulation FD presentations and other events tied to siRNA pipeline development.
The company’s disclosures also cover proxy materials for shareholder voting and governance, board composition, executive departures and appointments, committee changes, and the relationship between listed ADSs and ordinary shares. Clinical and business exhibits describe programs from the mRNAi GOLD platform, including SANRECO updates for divesiran in polycythemia vera and collaboration-related disclosures involving AstraZeneca.
Silence Therapeutics plc entered into a separation and release agreement with former executive Craig Tooman dated July 10, 2026, following his December 14, 2025 Separation Date. The company will provide $655,000 in 12 months of salary continuation, a $250,000 lump-sum severance payment, and reimbursements including $40,000 of legal fees, a $283,746.03 2025 bonus, $46,896.48 of healthcare premiums, and up to $20,000 of tax-provider fees.
Mr. Tooman’s equity awards will continue vesting for 45 days after the Separation Date, with extended post-termination option exercise periods of up to 24 months for options under the 2023 Equity Incentive Plan and 12 months for options under the 2018 Long Term Incentive Plan. Any unvested options may vest upon a change of control within 12 months after the Separation Date, conditioned on his continued compliance with the Separation Agreement, which also includes confidentiality, non-disparagement and non-solicitation covenants and a release of claims.
Silence Therapeutics plc large shareholder Richard Griffiths has updated his ownership in an Amendment No. 10 to his Schedule 13D. He now beneficially owns 30,844,458 ordinary shares, representing 21.7% of the company’s ordinary shares, based on 141,701,847 shares outstanding in the issuer’s last SEC filing.
The filing explains that this amendment reflects open-market transactions in the issuer’s American Depositary Shares (ADSs) together with dilution from an increase in share capital. Griffiths sold an aggregate of 1,544,374 ADSs between June 29, 2026 and July 6, 2026 for aggregate sales proceeds of $16. Each ADS represents, and at the holder’s option is convertible into, three ordinary shares of the issuer.
Silence Therapeutics plc 10% owner Richard Ian Griffiths reported a series of open-market sales of American Depositary Shares (ADSs) associated with his holdings. Across six transactions between June 29 and July 6, 2026, entities linked to him sold an aggregate of 1,544,374 ADSs.
The ADSs were sold indirectly through interests, including Cream Capital Limited, with Griffiths disclaiming beneficial ownership beyond his proportionate pecuniary interest. Following these transactions, he continued to report 10,281,486 ADSs held indirectly. Each ADS is immediately convertible into three ordinary shares for no consideration and has no expiration date.
Silence Therapeutics furnished an updated corporate presentation outlining progress across its RNA interference (siRNA) pipeline for rare blood and cardiometabolic diseases. The 8-K is a Regulation FD disclosure and the materials are furnished, not filed, under securities laws.
The presentation highlights divesiran for polycythemia vera, where a 21‑patient Phase 1 study showed marked reductions in phlebotomy dependence with a favorable safety profile. A 48‑patient, placebo‑controlled Phase 2 trial is fully enrolled, with topline results expected in 3Q 2026.
SLN312, an ANGPTL3‑targeting siRNA for dyslipidemia, showed robust lipid and ANGPTL3 reductions in Phase 1; Silence expects to regain global rights after Phase 1. Preclinical programs include SLN365 (GPR146) for familial hypercholesterolemia, targeting an IND in 2H 2027, and SLN098 (INHBE) for obesity and metabolic disease, with ~90% target knockdown in primates and a potential IND by 2027 year‑end.
Silence Therapeutics plc reports that shareholders approved nine resolutions at its 2026 Annual General Meeting held on June 16, 2026. Investors re‑appointed directors Rhonda Hellums and James Ede‑Golightly, with 47,160,731 and 52,112,045 votes cast in favor, respectively.
Shareholders gave advisory approval to executive compensation and the directors’ remuneration report, and adopted the 2025 U.K. statutory annual accounts and reports. They also ratified and re‑appointed PricewaterhouseCoopers LLP as both U.S. independent registered public accounting firm and U.K. statutory auditors, and authorized the Audit & Risk Committee to set the auditors’ remuneration. Application of Article 159 of the Company’s articles of association was also approved.
Silence Therapeutics plc reported new follow-up results from its Phase 1 SANRECO study of divesiran, an siRNA therapy for polycythemia vera, showing durable reductions in phlebotomy needs and potential quality-of-life benefits.
Among 21 phlebotomy-dependent patients, 80 phlebotomies were required in the six months before treatment versus only 5 during the active dosing period, all in patients with uncontrolled hematocrit above 45%. In the 16-week follow-up after the final dose, only 4 phlebotomies were reported, and for 14 patients with extended follow-up the median time to first phlebotomy was 287 days. Most patients saw improvements in MPN-10 symptom scores, and divesiran was generally well tolerated with mainly mild, transient injection-site reactions and no dose-limiting toxicities.
The ongoing randomized, placebo-controlled Phase 2 SANRECO study in 48 patients is testing 6 mg divesiran given every 6 or 12 weeks, with topline results expected in August 2026.
Silence Therapeutics plc filed a prospectus supplement to offer up to $100,000,000 of American Depositary Shares (ADSs) under an at-the-market sales agreement with Jefferies LLC dated May 18, 2026. Each ADS represents three ordinary shares. The offering is agent-led: Jefferies may sell ADSs from time to time, subject to market conditions and mutually agreed terms, and is entitled to up to a 3.0% commission. The prospectus notes 47,234,613 ADSs (141,703,840 ordinary shares) outstanding as of March 31, 2026, states an assumed illustrative price of $6.10 per ADS for dilution examples, and discloses net tangible book value metrics (historical $0.82 per ADS, as-adjusted $2.12 per ADS) and illustrative dilution of $3.98 per ADS. Use of net proceeds, if any, is for clinical development and general corporate purposes. The offering may be conducted as an "at-the-market" program and proceeds and number of ADSs sold are uncertain.
Silence Therapeutics plc entered into a new Open Market Sale Agreement with Jefferies LLC, establishing an at-the-market program for American Depositary Shares under its Form S-3 shelf registration statement. This replaces and terminates the company’s prior Open Market Sale Agreement with Jefferies.
The company also updated its tax risk disclosures to state that, after further analysis, it currently believes it was not classified as a passive foreign investment company for the taxable year ended December 31, 2025, while emphasizing that its PFIC status remains a complex, annual, facts-based determination.
Silence Therapeutics plc filed a shelf registration to offer up to $300,000,000 of ordinary shares, which may be represented by American Depositary Shares (ADSs). The prospectus states that up to $100,000,000 of ADSs are included within the $300,000,000 shelf. Each ADS represents three ordinary shares. The registration is a base shelf prospectus; specific offering amounts, prices and distribution methods will be set forth in future prospectus supplements.