26 Sept 2018

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


("Sareum" or "the Company")

Potent, selective small molecule inhibitor of TYK2/JAK1 selected for further development as potential treatment for certain types of leukaemia, lymphoma and solid tumour

Sareum Holdings plc (AIM: SAR), the drug discovery and development company, announces that it has made the formal selection of a development candidate from its TYK2 inhibitor programme to advance through preclinical development as a potential new targeted therapy for certain cancers.

The candidate molecule, SDC-1802, demonstrated high selectivity for TYK2 and JAK1 kinases (particularly over related JAK2 and JAK3). SDC-1802 shows compelling efficacy in blocking cancer cell proliferation in cellular and disease models of T-cell acute lymphoblastic leukaemia (T-ALL) and B-cell lymphoma, the potential for once-daily oral dosing and a good early safety profile. In addition, Sareum has generated encouraging evidence to suggest that these molecules can function as cancer immunotherapy by modulating the host’s immune system to block tumour cell proliferation in disease models of certain kidney, colon, skin and pancreatic cancers.

Sareum intends to progress SDC-1802 into preclinical development (and pending satisfactory progress) into human clinical trials which could begin in 2020. The Company owns the commercialisation rights for these candidates and other dual TYK2/JAK1 inhibitors with profiles optimised for oncology indications.

Sareum announced on 10 September 2018 that it is also advancing SDC-1801 as a distinct dual TYK2/JAK1 inhibitor for the potential treatment of autoimmune diseases, including psoriasis, rheumatoid arthritis, inflammatory bowel disease and lupus. SDC-1802 also has the potential to act as a back-up molecule for these autoimmune indications.

Dr Tim Mitchell, CEO of Sareum, commented: “We are very pleased to have formally selected lead candidates from our TYK2 inhibitor programme for both cancer and autoimmune diseases. The candidates are distinct small molecules with attractive and highly competitive profiles for development in their respective indications. Both candidates have produced exciting results in preclinical disease models and we believe present valuable opportunities for licensing and/or further development. Our focus is now to advance both candidates into clinical studies, which we anticipate beginning in 2020.”

For further information, please contact: 

Sareum Holdings plc


Tim Mitchell

01223 497 700

WH Ireland Limited (Nominated Adviser)

Chris Fielding / James Sinclair-Ford

020 7220 1666

Hybridan LLP (Broker)


Claire Noyce

020 3764 2341

Citigate Dewe Rogerson (Media enquiries)


 Shabnam Bashir/ Mark Swallow/ David Dible

 020 7638 9571

Notes for editors: 

About TYK2 and JAK1 kinases

TYK2 and JAK1 are members of the Janus Kinase (JAK) family of protein kinase enzymes with roles in tumour cell proliferation in certain cancers and pro-inflammatory responses in autoimmune diseases. Members of the JAK family are the targets of several marketed and clinical-stage drugs for cancer and autoimmune diseases, although there are currently no marketed products specifically targeting TYK2. 

About Sareum Holdings plc

Sareum is a drug discovery and development company delivering targeted small molecule therapeutics, focusing on cancer and autoimmune disease. The Company generates value through licensing its candidates to international pharmaceutical and biotechnology companies at the preclinical or early clinical trials stage.

Sareum’s leading clinical-stage programme, SRA737, a novel Checkpoint kinase 1 (Chk1) inhibitor licensed to NASDAQ-listed Sierra Oncology, is in Phase 2 clinical trials targeting ovarian and other advanced cancers. The key role of Chk1 in cancer cell replication and DNA damage repair suggests that SRA737 may have broad application as a targeted therapy in combination with other oncology and immune-oncology drugs in genetically defined patients.

Sareum is also advancing internal programmes focused on distinct dual tyrosine kinase 2 (TYK2) /Janus kinase 1 (JAK1) inhibitors through preclinical development as therapies for autoimmune diseases and cancers. TYK2 and JAK1 have roles in pro-inflammatory responses in autoimmune diseases (e.g. psoriasis, rheumatoid arthritis, inflammatory bowel diseases and lupus) and tumour cell proliferation in certain cancers (e.g. T-cell acute lymphoblastic leukaemia and some solid tumours). The Company is targeting first human clinical trials in each indication in 2020.

The Company also has an Aurora+FLT3 inhibitor targeting haematological cancers, which is at the preclinical development stage.

Sareum Holdings plc is listed on the AIM market of the London Stock Exchange, trading under the ticker SAR. For further information, please visit www.sareum.co.uk

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