Sareum notes new preclinical data demonstrating durable tumour regression with SRA737 plus low dose chemotherapy combined with anti-PD-L1 immunotherapy in small cell lung cancer model presented at AACR 2019

Sareum Holdings plc (AIM: SAR), the specialist small molecule drug development business, notes that Sierra Oncology (“Sierra”), the licence holder advancing clinical cancer candidate SRA737, announced late yesterday that new preclinical data for SRA737, its Chk1 inhibitor, plus low dose gemcitabine (LDG), in combination with anti-PD-L1 immunotherapy, has been reported in a late-breaking oral presentation at the American Association of Cancer Research (AACR) Annual Meeting 2019, being held in Atlanta, GA, USA from 29 March to 3 April 2019.

In the study, SRA737+LDG demonstrated significant anti-tumour activity when combined with anti-PD-L1 immunotherapy in a mouse model of small cell lung cancer (SCLC), resulting in durable tumour regressions. 10/10 examples showed tumour regression at the end of the 21-day treatment period and 8/10 showed sustained complete response after a further 39 days without further treatment.

These findings suggest that the combination of anti-PD-L1 immunotherapy with the SRA737+LDG regimen may represent the optimal implementation of these agents, leading to a dramatic anti-tumour activity and provide a strong rationale for combining these agents with the SRA737+LDG regimen to enhance clinical response rates.

Dr Tim Mitchell, CEO of Sareum Holdings plc, said: “The model data presented are very exciting with all examples treated with SRA737, LDG and anti-PD-L1 showing tumour regression and 80% having a complete response, with no detectable cancer. This provides a clear early demonstration of the potential of SRA737+LDG to enhance anti-PD-L1 immunotherapy in small cell lung cancer, a cancer type where such immunotherapies have shown limited benefit. We will follow the progress of studies using this novel combination approach with great interest.”

Lung cancer is by far the leading cause of cancer death among both men and women and about 10-15% are SCLC. Each year, more people die of lung cancer than from colon, breast, and prostate cancers combined. According to the American Cancer Society, there about 228,150 new cases of lung cancer and about 142,670 deaths from lung cancer in the United States in 2019.

The full announcement by Sierra Oncology can be found by clicking here.

Summary slides from this presentation are available here.

A late-breaking abstract details highly significant and timely findings in any area of cancer research that were not available at the time of the regular abstract deadline. Only those abstracts that are deemed to be of high scientific priority will be accepted for presentation at the meeting.

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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 visitwww.sareum.co.uk

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