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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 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.
Silence Therapeutics plc reported a smaller net loss for the three months ended March 31, 2026 as it advanced its RNAi pipeline and absorbed changes in a key collaboration. Revenue from its AstraZeneca alliance was $0.4 million, up from $0.1 million a year earlier.
Research and development costs fell to $9.1 million from $20.8 million, mainly as Phase 3 readiness work for zerlasiran wound down and headcount declined. Net loss narrowed to $15.0 million (loss per share $0.11) from $28.5 million (loss per share $0.20).
Cash, cash equivalents and short-term investments totaled $70.1 million, and the company believes this will fund operations into 2028, though additional capital will be needed for later-stage development. AstraZeneca decided not to develop SLN312 beyond Phase 1, and Silence will regain full global rights while evaluating further clinical plans. Lead asset divesiran is in a fully enrolled Phase 2 PV trial with topline data expected in the third quarter of 2026, and zerlasiran is Phase 3 ready as the company seeks a partner.
Silence Therapeutics plc reported first quarter 2026 results, showing higher collaboration revenue and a much narrower loss as it advances its siRNA pipeline. Collaboration revenue from AstraZeneca rose to $0.4 million from $0.1 million a year earlier.
Research and development expenses fell to $9.1 million from $20.8 million, largely after completing zerlasiran Phase 3 readiness in 2025. Net loss improved to $15.0 million, or $0.11 per share, compared with a $28.5 million loss, or $0.20 per share, in the prior-year quarter. The company held $70.1 million in cash, cash equivalents and short-term investments as of March 31, 2026, and its Phase 2 SANRECO trial of divesiran in polycythemia vera remains on track for topline results in August 2026.
Silence Therapeutics plc has released proxy materials for its 2026 Annual General Meeting, a hybrid meeting on June 16, 2026 in Hoboken, NJ and online. Shareholders will vote on nine ordinary resolutions, including re-appointing directors Rhonda Hellums and James Ede-Golightly, an advisory say-on-pay, and multiple auditor items involving PricewaterhouseCoopers LLP.
Other proposals cover receiving and adopting the 2025 U.K. Annual Report, approving the U.K. statutory directors’ annual report on remuneration, and continuing takeover protections in Article 159 of the articles of association. Ordinary resolutions pass with a simple majority of votes cast. There were 141,703,839 ordinary shares issued and outstanding as of April 24, 2026.
Silence Therapeutics plc is a UK-based biotechnology company developing short interfering RNA (siRNA) medicines using its mRNAi GOLD™ liver-targeted platform. Its lead rare disease program, divesiran (SLN124), is in a fully enrolled Phase 2 SANRECO trial for polycythemia vera, with topline results expected in the third quarter of 2026.
Cardiometabolic pipeline assets include zerlasiran (SLN360), a Phase 3–ready siRNA targeting Lp(a) for cardiovascular disease, SLN312 targeting ANGPTL3, SLN365 for cholesterol via GPR146, and SLN098 for obesity via INHBE, all designed for potent, infrequent subcutaneous dosing. The company believes existing cash, cash equivalents and anticipated milestone payments from current collaborations can fund operations into 2028.
Silence has collaboration histories with AstraZeneca and Hansoh. AstraZeneca advanced SLN312 into Phase 1 with multiple milestone payments but decided on March 4, 2026 not to pursue development beyond Phase 1, after which Silence will regain full global rights. Hansoh paid upfront and milestone amounts on three siRNA targets but elected in December 2024 not to continue development, leaving Silence with worldwide rights to those programs.