SLN.L Regulatory News (SLN)

Mallinckrodt to make an equity invesTment in SILENCE THERAPEUTICS as part of a collaboration TO DEVELOP AND COMMERCIALIZE RNAi THERAPEUTICS FOR COMPLEMENT-MEDIATED DISEASES

- Mallinckrodt Chief Scientific Officer Steven Romano, M.D. joins Silence Board as non-executive Director -

LONDON, United Kingdom and STAINES-UPON-THAMES, July 18, 2019 /PRNewswire/ -- Silence Therapeutics plc (LON: SLN), a leader in the discovery, development and delivery of novel RNA[1] interference (RNAi) therapeutics for the treatment of serious diseases and Mallinckrodt plc (NYSE: MNK), a global biopharmaceutical company, announce that, further to the collaboration announced earlier today, Mallinckrodt, acting through a subsidiary company, has agreed to make an equity investment of $5 million in Silence Therapeutics.

Mallinckrodt is subscribing for a total of 5,062,167 new ordinary shares at an issue price of 79p per share, representing a 10 percent premium to Silence's 20-day, volume-weighted average price. Application will be made to the London Stock Exchange for the admission of the 5,062,167 new ordinary shares to be subscribed for trading on AIM[2]. It is expected that dealings will commence at 8:00 a.m. BST[3] on 24 July 2019. Immediately following admission, Mallinckrodt's shareholding will represent 6.5 percent of Silence Therapeutics' enlarged, issued share capital which will be 77,285,652 ordinary shares.

As part of this equity investment Mallinckrodt will take a non-executive Director seat on the Silence Board of Directors, and it has been proposed that Steven Romano, M.D., Executive Vice President and Chief Scientific Officer at Mallinckrodt fulfill this position. A further announcement, including the disclosures required under Rule 17 and Schedule Two paragraph (g) of the AIM Rules for Companies, will be made at the time of Dr. Romano's appointment to the Board.

The separate collaboration between Mallinckrodt and Silence Therapeutics announced earlier today will allow the companies to develop and commercialize RNAi drug targets designed to inhibit or silence the complement cascade, a group of proteins that are involved in the immune system and that play a role in the development of inflammation. These proteins are known to contribute to the pathogenesis of many diseases, including autoimmune diseases.

ABOUT SILENCE

Silence Therapeutics is developing a new generation of medicines by harnessing the body's natural mechanism of RNA interference, or RNAi, within its cells. Its proprietary technology can selectively inhibit any gene in the genome, specifically silencing the production of disease-causing proteins. Using its enabling delivery systems, it has achieved an additional level of specificity by delivering its therapeutic RNA molecules exclusively to target cells. Silence's proprietary RNA chemistries and delivery systems are designed to improve the stability of our molecules and enhance effective delivery to target cells, providing a powerful modular technology well suited to tackle life-threatening diseases. Silence Therapeutics remains focused and is determined to be responsive to creating shareholder value as well as the appropriate growth and development of its business. Silence Therapeutics continues to assess a number of options in addition to its organic plan which it believes would be additive to the Company's future growth prospects and shareholder value, which may include equity fundraisings as well as other strategic licensing and collaboration opportunities. For more information, please visit https://www.silence-therapeutics.com/.

ABOUT MALLINCKRODTMallinckrodt is a global business consisting of multiple wholly owned subsidiaries that develop, manufacture, market and distribute specialty pharmaceutical products and therapies. The company's Specialty Brands reportable segment's areas of focus include autoimmune and rare diseases in specialty areas like neurology, rheumatology, nephrology, pulmonology and ophthalmology; immunotherapy and neonatal respiratory critical care therapies; analgesics and gastrointestinal products. Its Specialty Generics reportable segment includes specialty generic drugs and active pharmaceutical ingredients. To learn more about Mallinckrodt, visit www.mallinckrodt.com.

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Cautionary Statements Related to Forward-Looking Statements

Mallinckrodt

This release includes forward-looking statements concerning Mallinckrodt's collaboration with Silence, including expectations regarding future research and development plans, potential milestone payments and commercial arrangements and the potential impact on patients. The statements are based on assumptions about many important factors, including the following, which could cause actual results to differ materially from those in the forward-looking statements: uncertainties inherent in research and development, including clinical trial results; satisfaction of regulatory and other requirements; actions of regulatory bodies and other governmental authorities; changes in laws and regulations; issues with product quality, manufacturing or supply, or patient safety issues; and other risks identified and described in more detail in the "Risk Factors" section of Mallinckrodt's most recent Annual Report on Form 10-K and other filings with the SEC, all of which are available on its website. The forward-looking statements made herein speak only as of the date hereof and Mallinckrodt does not assume any obligation to update or revise any forward-looking statement, whether as a result of new information, future events and developments or otherwise, except as required by law.

Silence

The information contained within this announcement is deemed by the Silence Therapeutics plc to constitute inside information as stipulated under the Market Abuse Regulation (EU) No. 596/2014. Upon the publication of this announcement via the Regulatory Information Service, this inside information is now considered to be in the public domain.

CONTACTS

MALLINCKRODT

Investor RelationsDaniel J. Speciale, CPAVice President, Investor Relations and IRO

314-654-3638

daniel.speciale@mnk.com

MediaDaniel Yunger

Kekst CNC

212-521-4879

mallinckrodt@kekstcnc.com

SILENCE THERAPEUTICS

Dr. David Horn Solomon, Chief Executive Officer

Mr. Iain Ross, Non-Executive Chairman

+44 (0) 20 3457 6900

Peel Hunt/LLP (Nominated Adviser and Broker)

James Steel/Oliver Jackson

+44 (0) 20 7418 8900

European IR

Consilium Strategic Communications

Mary-Jane Elliott/Chris Welsh/Angela Gary

silencetherapeutics@consilium-comms.com

+44 (0) 20 3709 5700

US IR

Westwicke Partners

Peter Vozzo

Peter.vozzo@westwicke.com

442-213-0505

Mallinckrodt, the "M" brand mark and the Mallinckrodt Pharmaceuticals logo are trademarks of a Mallinckrodt company. Other brands are trademarks of a Mallinckrodt company or their respective owners. © 2019 Mallinckrodt. 7/19