Alnodesertib

U.S. Fast Track designation of ART6043 underpinned by promising clinical data to date and high unmet need in gBRCA-mutated HER2-negative breast cancer Artios is launching a global randomized Phase 2 study to evaluate ART6043 in patients with BRCA-mutant HER2-negative breast cancer who are eligible to receive a PARP inhibitor CAMBRIDGE, United Kingdom and NEW YORK, February 23, 2026 – Artios Pharma Limited (“Artios”), a clinical-stage biopharmaceutical company pioneering the development of new classes of DNA Damage Response (DDR) medicines to deliver meaningful survival benefits for patients with cancer, today announced that the U.S. Food and Drug Administration (FDA) granted Fast Track designation to its potentially first-in-class DNA polymerase theta (Polθ) inhibitor, ART6043, in combination with the PARP inhibitor, olaparib, for the treatment of adult patients with germline BRCA-mutated (gBRCAm) HER2-negative locally advanced or metastatic breast cancer who have received no prior treatment with a PARP inhibitor. “Breast cancer remains the second leading cause of cancer death in women in the United States. Granting of U.S. Fast Track designation is an important recognition of ART6043’s clinical pro treat gBRCAm HER2-negative breast cancer and supports our mission to rapidly deliver potential first-in-class therapies to patients who have limited treatment options,” said Mike Andriole, Chief Executive Officer of Artios . “Importantly, breast cancer patients with a BRCA mutation often develop resistance to treatment with a PARP inhibitor alone. There remains a significant need to improve clinical outcomes and rates of survival through inhibition of Polθ.” The designation was granted based on data from the ongoing, first-in-human, Phase 1/2a study ( NCT05898399 ), evaluating ART6043 in combination with olaparib in patients with advanced solid tumors harboring mutations in DDR pathways, including gBRCAm HER2-negative breast cancer. In data presented at the European Society for Medical Oncology (ESMO) Congress 2025, ART6043 demonstrated an attractive tolerability profile, expected PK/PD activity, and promising clinical signals. “gBRCA-mutated HER2-negative breast cancer presents significant treatment challenges due to its frequently aggressive nature and high risk of recurrence, often due to BRCA reversions, with patients requiring intensive therapy,” said Ian Smith, Chief Medical Officer of Artios . “In our ongoing Phase 1/2a study, ART6043, in combination with olaparib, has shown encouraging clinical activity in the relevant genetic background, together with a favorable tolerability and pharmacology profile. These early results support ART6043 as a potential new targeted therapy capable of removing a cancer cell’s reliance on Polθ as a DNA repair mechanism to enhance anti-tumor activity in a well-defined patient population.” “Our experiments to date with ART6043 have been rationally designed following our team’s pioneering work with the industry’s first PARP inhibitor and recognizing that inhibition of Polθ may enhance the cancer cell killing effects of PARP inhibition and overcome key mechanisms of resistance to improve survival in these patients,” added Graeme Smith, Chief Scientific Officer of Artios. The FDA’s Fast Track program is designed to facilitate the development and expedite the review of investigational drugs that demonstrate the potential to address unmet medical needs in serious or life-threatening conditions. Product candidates with Fast Track designation are eligible for priority review and accelerated approval if relevant criteria are met. This designation will enable Artios to interact more frequently and earlier with the FDA to discuss ART6043’s development path. About ART6043 ART6043 is a potential first-in-class, selective, orally bioavailable, small‑molecule inhibitor of the polymerase domain of DNA polymerase theta (Polθ), a DNA repair enzyme that is preferentially expressed in cancer cells but is virtually absent in most healthy tissues. By inhibiting Polθ, ART6043 targets microhomology-mediated end joining (MMEJ) to exploit tumor dependence on error-prone DNA repair, with broad rationale for use as monotherapy and in combination with PARP inhibition and other DNA‑damaging modalities. Artios’ differentiated approach is to evaluate ART6043 with olaparib in molecularly defined solid tumors, including settings with BRCA variants and PARP inhibitor resistance, to enhance target engagement and anti-tumor activity while maintaining tolerability. About Artios Pharma Ltd. Artios’ mission is to develop new classes of medicines that harness DNA Damage Response (DDR) pathways, targeting DNA replication stress and synthetic lethality, to deliver meaningful survival benefits for patients with cancer. Its three potentially first-in-class programs, each with a novel mechanism of action, include ATR inhibitor alnodesertib, the DNA polymerase theta (Polθ) inhibitor ART6043, and a preclinical portfolio of DDRi-ADC candidates with novel payloads. Together, these programs are designed to eliminate cancer cells’ survival mechanisms, driving cancer cell death and improving clinical outcomes. Visit our website at to learn more about Artios. For more information, please contact: Trophic Communications Jacob Verghese or Verena Schossmann Tel: +49 151 7441 6179 Email: artios@trophic.eu