Update re: FLT3+Aurora Kinase Inhibitor Programme

SAREUM HOLDINGS PLC

("Sareum" or "the Company")

Update re: FLT3+Aurora Kinase Inhibitor Programme

Cambridge, UK, 8 January 2021 - Sareum Holdings plc (AIM: SAR), the specialist drug development company delivering targeted small molecule therapeutics to improve the treatment of cancer and autoimmune diseases, reports that the licensing partner (the "Licensee") for its FLT3+Aurora kinase programme (the "FLT3 programme") has decided not to exercise its option to continue the development of the programme. Sareum received formal confirmation of the Licensee's decision today. Worldwide rights to the FLT3 programme, as well as data relating to progress made by the Licensee, will therefore revert to Sareum.

As announced on 26 March 2020, the previously de-prioritised FLT3 programme was licensed to a China-based specialty pharma company for which Sareum received an upfront payment of approximately £50,000. While the Licensee has improved the bioavailability of the lead compound in the FLT3 programme, it has been unable to achieve the level needed to trigger the milestone under the licensing agreement and, as a result, it has decided to terminate the licence agreement and relinquish its rights to the FLT3 programme, with no further payments being due to Sareum.

Sareum's CEO, Dr Tim Mitchell, commented:

"We will review the data and progress made with the programme by our Chinese partner over the coming weeks and will evaluate options for re-partnering the FLT3 programme. While early studies with our FLT3+Aurora kinase inhibitors were promising, formulation continues to be a challenge. Our clear priority focus remains on advancing our proprietary TYK2/JAK1 programmes and, in the near-term, on completing the preclinical work needed for the first Clinical Trial Application during the first quarter of the year. Achieving this important milestone will be a key step in generating shareholder value from our TYK2/JAK1 pipeline."

This announcement contains inside information for the purposes of Article 7 of Regulation 596/2014.

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About Sareum

Sareum is a specialist drug development company delivering targeted small molecule therapeutics to improve the treatment of cancer and autoimmune diseases. The Company aims to generate value through licensing its candidates to international pharmaceutical and biotechnology companies at the preclinical or early clinical trials stage.

Sareum is advancing internal programmes focused on distinct dual tyrosine kinase 2 (TYK2) / Janus kinase 1 (JAK1) inhibitors through preclinical development as therapies for autoimmune diseases, including the 'cytokine storm' immune system overreaction to Covid-19 and other viral infections, (SDC-1801) and cancer immunotherapy (SDC-1802).

Sareum also has an economic interest in SRA737, a clinical-stage oral, selective Checkpoint kinase 1 (Chk1) inhibitor that targets cancer cell replication and DNA damage repair mechanisms. Preliminary Phase 2 and comprehensive preclinical data suggest SRA737 may have broad application in combination with other oncology and immune-oncology drugs in genetically defined patients.

SRA737 was discovered and initially developed by scientists at The Institute of Cancer Research in collaboration with Sareum, and with funding from Sareum and Cancer Research UK. SRA737 was licensed by CRT Pioneer Fund (CPF) to Sierra Oncology Inc. Sierra continues to explore options that would enable the development of SRA737 to advance.

Sareum Holdings plc is listed on the AIM market of the London Stock Exchange, trading under the ticker SAR. For further information, please visit the Company's website at www.sareum.com