Artios’ small molecule Polθ inhibitor elicits BRCA-gene synthetic lethality and PARP inhibitor synergyGenetic screening reveals biomarkers within the PARP inhibitor resistance setting to enable patient stratification in clinical development of Polθ inhibitorsArtios’ Polθ program on-track for first-in-human studies before year-end 2021Polθ program developed using Artios’ DDR-based platform and small molecule drug design capabilities CAMBRIDGE, United Kingdom and NEW YORK, June 17, 2021 (GLOBE NEWSWIRE) — Artios Pharma Limited (Artios), a leading DNA Damage Response (DDR) company exploiting a broad DDR-based platform and small molecule drug design capabilities to develop a diverse pipeline of product candidates for the treatment of cancer, today announced the publication of a peer reviewed article titled, “Polθ inhibitors elicit BRCA-gene synthetic lethality and target PARP inhibitor resistance” in Nature Communications. Using novel small molecule tool compounds, the preclinical data generated in collaboration with researchers at the Institute for Cancer Research, London, and Cancer Research U.K., validates the Company’s approach to developing a potential first-in-class Polθ inhibitor, which demonstrated potent, selective Polθ inhibition, BRCA-gene synthetic lethality in a potentially PARP-resistant setting, and PARP inhibitor synergy. Professor Chris Lord, Professor of Cancer Genomics at The Institute of Cancer Research, London and study co-leader, said: “Polθ is an ideal DNA damage response drug target as it is tumor specific, overexpressed in many tumors and found at low levels in healthy tissues. These results show that Polθ inhibitors exhibited exquisite selectivity and on-target activity, affecting only Polθ-Mediated End Joining and not other forms of DNA repair. This specificity, combined with demonstrated synthetic lethality with BRCA mutations, as well as synergy with a PARP inhibitor, suggest small molecule Polθ inhibition has broad utility for targeted clinical development in genetic backgrounds that are reliant on Polθ activity. I look forward to seeing how Polθ inhibitors perform in clinical trials and hope they will be able to benefit patients by opening up a new way of overcoming drug resistance.” Dr. Graeme Smith, Chief Scientific Officer of Artios Pharma, said: “This preclinical dataset further strengthens the scientific foundation of our Polθ inhibitor program. This publication is a testament to the deep scientific heritage and expertise in DNA damage response that drives the Artios discovery platform and pipeline. The extensive efforts of our team have delivered insights into the genetics and mechanisms that underlie the activity of Polθ inhibitors, leaving us well positioned to pursue a strategic development plan in the clinic across a wide range of opportunities.” Dr. Niall Martin, Chief Executive Officer at Artios Pharma, said: “These published results provide a clear rationale for three high-value opportunities for Polθ inhibitors: in the monotherapy setting to treat Polθ dependent cancers; in combination with PARP inhibitors to expand the utility of this important drug class; and in combination with DNA damaging therapies such as ionizing radiation to provide effective and widespread use of these agents. We are on track to launch our Polθ clinical program before year end, building upon our strong execution which includes strategic partnerships with Merck KGaA and Novartis, and our ongoing Phase 1 study of ART0380, a potential best-in-class ATR inhibitor.” Publication highlights include: Artios’ small molecule Polθ inhibitors provided nanomolar potent, selective, allosteric inhibition of the polymerase function of DNA polymerase Polθ, selectively inhibiting Theta-Mediated End Joining DNA repair without targeting Non-Homologous End Joining or Homologous Recombination.Inhibiting Polθ elicited DNA damage and synthetic lethality in BRCA1- or BRCA2-mutant tumor cells and enhanced the effects of a PARP inhibitor.Genetic screening revealed defects in the Shieldin complex causing both PARP inhibitor resistance and synthetic lethality with Polθ inhibition, thus identifying a subset of PARP inhibitor resistant disease with the potential to be specifically targeted with Polθ inhibitors.Sensitivity of BRCA1, Shieldin-defective tumours to Polθ inhibition was confirmed in vivo laying the foundations for preclinical and clinical development. For more information, please contact: Investor Contact: Abid Ansari, Chief Financial OfficerE: Abid.Ansari@artiospharma.com Media Contact:LifeSci AdvisorsLigia Vela ReidE: lvela-reid@lifesciadvisors.com About Artios Pharma Limited Artios is a leading DNA Damage Response (DDR) company focused on developing first-in-class treatments for cancer. The Company is led by an experienced scientific and leadership team with proven expertise in DDR drug discovery, including the discovery and early development of the PARP inhibitor olaparib. It has a unique partnership with Cancer Research UK (CRUK), and collaborations with leading DNA repair researchers worldwide, such as The Institute of Cancer Research (ICR), London, the Netherlands Cancer Institute (NKI) and the Crick Institute, London. Artios is building a pipeline of next-generation DDR programmes to target hard to treat cancers, including its ATR inhibitor ART0380 in treating DDR defective tumours, which is in a Phase I clinical study, and the potential first-in-class Pol theta inhibitor ART4215 for monotherapy and combination treatments. In December 2020, Artios entered into a collaboration agreement with Merck KGaA, Darmstadt, Germany to identify and develop precision oncology medicines targeting nucleases. Merck KGaA, Darmstadt, Germany has the right to opt into exclusive development and commercialization of compounds on up to eight targets and Artios to receive up to US$860 million total milestones per target. In April 2021, Artios entered into a collaboration with Novartis to identify DDR targets to use with Novartis’ proprietary radioligand therapies with Artios receiving a US$20 million up-front payment in addition to near term research funding to support the collaboration. Artios is eligible to receive up to $1.3 billion in discovery, development, regulatory and sales-based milestones in addition to royalty payments. Artios is backed by blue chip investors including: AbbVie Ventures, Andera Partners, Arix Bioscience plc, IP Group plc, Life Science Partners (LSP), M Ventures, Novartis Venture Fund (NVF), Pfizer Ventures and SV Health Investors. Artios is based at the Babraham Research Campus in Cambridge, UK, with an office in New York City, USA.