Sareum Regulatory News (SAR)

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

Sareum Holdings PLC

("Sareum" or the "Company")

Sareum notes that positive preliminary efficacy data from Phase 1/2 clinical trials with SRA737 in advanced cancer were presented at ASCO 2019 - potential path to registration outlined

· 30% response rate for SRA737 + low dose gemcitabine (LDG) in anogenital cancer

· Anti-cancer activity demonstrated across multiple indications and genetic profiles

· Sierra Oncology to discuss clinical findings and next steps for SRA737 at Analyst & Investor Event and live webcast today at 12:00 BST

Sareum Holdings plc (AIM: SAR), the specialist small molecule drug development business, notes that Sierra Oncology (the licence holder for Chk1 inhibitor SRA737) reported positive preliminary clinical data from its two first-in-human Phase 1/2 studies of SRA737 as monotherapy and as SRA737+LDG (SRA737 potentiated by low dose gemcitabine) at the 2019 Annual Meeting of the American Society of Clinical Oncology (ASCO) in Chicago, IL. Anti-cancer activity was demonstrated across multiple indications and genetic contexts, with SRA737+LDG specifically achieving a notable 30% response rate in anogenital cancer patients.

The data and further analyses can be found in the announcement made on Saturday 1 June by Sierra Oncology (click here) and in both posters, which are available here. A live webcast of the Analyst & Investor Event taking place today at 12:00 BST can be accessed by clicking here.

Dr Tim Mitchell, CEO of Sareum Holdings, said: "We are extremely encouraged by the preliminary clinical data that Sierra announced from its clinical programme with SRA737 at ASCO over the weekend. The results demonstrate the exciting potential of SRA737 in patients whose cancer type and genetic profile may confer and enhance sensitivity to this novel drug candidate, and open pathways for its advancement into the next stages of development towards registration. We look forward to providing updates on this exciting prospect as further progress is made and important development milestones are reached."

SRA737 was discovered and initially developed by scientists at The Institute of Cancer Research, London, UK in collaboration with Sareum, and with funding from Cancer Research UK. SRA737 was licensed to Sierra Oncology for up to $328.5 million plus royalties by co-investment partner, CRT Pioneer Fund. Sareum is eligible to receive up to $88 million in milestone payments, plus sales royalties as SRA737 advances.

Commenting further on the clinical results, Dr Mitchell, added: "Sierra has designed its clinical trials with SRA737 to make use of the most advanced concepts in tumour evaluation with the goal of identifying indications and gene mutations most likely to sensitise tumours to SRA737, and thereby guide patient selection in future registration-oriented trials.

"The most striking efficacy findings from these initial clinical trials were in patients receiving the SRA737+LDG combination, where sub-therapeutic LDG was shown to potentiate the activity of SRA737, as hypothesised. In this trial, a clear efficacy signal was observed across patients with anogenital/cervical cancer, with the most pronounced anti-tumour activity seen in anogenital cancer patients. Second-line metastatic anogenital cancer represents a significant unmet medical need with no approved therapies. Based on the results, the authors suggest SRA737+LDG could represent a potentially efficacious treatment option for these patients and warrants additional registration-intent studies.

"In the SRA737 monotherapy study, there was evidence of anti-tumour activity (tumour reduction) in subjects with high-grade serous ovarian cancer (HGSOC), colorectal, prostate and non-small cell lung cancer, with HGSOC appearing to be the most sensitive tumour type. Durable responses (stable disease ≥ 4 months) were observed in all expansion cohorts except head and neck cancer.

"In both reported trials, recommended doses of SRA737 and SRA737+LDG were shown to be safe and well tolerated, highlighting the class-leading safety profile of SRA737. The emerging insight to the correlation between clinical response with genetic profile also demonstrates the potential for patient selection and combining SRA737 with other therapeutic approaches under consideration for further investigation, such as PARP inhibitors and immune checkpoint blockade."

Professor Udai Banerji, Deputy Director of the Drug Development Unit at The Institute of Cancer Research, London and The Royal Marsden NHS Foundation Trust, said: "These studies have shown the potential of SRA737 as a possible future treatment for a range of cancer types, with some encouraging results in combination with low-dose chemotherapy in anogenital cancers.

"It's a pleasure to see a drug discovered here at the ICR and progressed through development with our partners show potential as a future treatment. Hopefully, further trials will firmly establish the effectiveness of the drug and provide a new option for patients for whom new options are urgently needed.

"Now that the dose and schedules of administration have been established in cancer patients, it will be possible to explore further combinations of SRA737 with other drugs across different cancers where very interesting preclinical data has been seen."

Professor Paul Workman, Chief Executive of The Institute of Cancer Research, London, said: "At the ICR, we believe that the future of cancer treatment is precision medicines, increasingly used as part of drug combinations, that exploit genetic weaknesses within cancer to overcome or delay drug resistance. The Chk1 inhibitor SRA737, which was discovered at the ICR with our partners Cancer Research UK and Sareum and is now being taken forward by Sierra Oncology, is an excellent example of such an innovative, highly targeted treatment. I am delighted to see the presentation of these results which indicate that SRA737 has the potential as part of combination therapy to benefit some patients with cancers of the anus and genitals - a group of diseases for which there are few therapeutic options."

An announcement on the results by the ICR can be found here

ASCO 2019 Poster Presentations

Title: A first-in-human phase I/II trial of SRA737 (a Chk1 Inhibitor) in subjects with advanced cancer

Abstract: 3094, Poster #: 86

Title: A phase I/II first-in-human trial of oral SRA737 (a Chk1 inhibitor) given in combination with low-dose gemcitabine in subjects with advanced cancer

Abstract: 3095, Poster #: 87

Both posters can be accessed here.

SRA737 Analyst & Investor Event

Sierra Oncology will host an Analyst and Investor Event today from 12:00-13:00 BST to discuss the clinical findings and potential next steps in the development strategy for SRA737. The event will feature presentations by two distinguished oncologists:

· Professor Johann de Bono, Regius Professor of Cancer Research, Head of the Division of Clinical Studies and Professor in Experimental Cancer Medicine at The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust; and

· Dr Rebecca Kristeleit, Clinical Senior Lecturer and Honorary Consultant Medical Oncologist at University College London (UCL) Cancer Institute & UCLH Dept. of Oncology, a leading expert in gynaecological malignancies.

Details for joining the live webcast are available here and an archive of the presentation will be accessible after the event through www.sierraoncology.com.

For further information, please contact: 

Notes for editors: 

Sareum is a specialist drug development company delivering targeted small molecule therapeutics, to improve the treatment of 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 (SDC-1801) and cancers (SDC-1802). 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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