Onxeo to Present New Preclinical Data Highlighting AsiDNA™’s Ability to Fight Tumor Resistance and Protect From Anticancer Treatment Toxicity at AACR Annual Meeting 2022

• AsiDNA™ proven to overcome resistance to tyrosine kinase inhibitors in lung cancer models
• AsiDNA™ proven to protect healthy cells when combined with conventional antitumor treatments

PARIS--(BUSINESS WIRE)-- Regulatory News:

Onxeo S.A. (Euronext Growth Paris: ALONX, First North Copenhagen: ONXEO), (“Onxeo” or “the Company”), a clinical-stage biotechnology company specializing in the development of innovative drugs targeting tumor DNA Damage response (DDR), today announced that it will present new preclinical data confirming AsiDNA™’s abilities to protect from anticancer treatment toxicity and fight tumor resistance during poster and oral sessions at the upcoming American Association for Cancer Research Annual Meeting (AACR Annual Meeting 2022, April 8-13, 2022).

The oral presentation will describe how AsiDNA™ efficiently prevented the emergence of resistances to tyrosine kinase inhibitors in several models of targetable oncogenic addiction and will point to the therapeutic opportunity of combining AsiDNA™ and TKI (tyrosine kinase inhibitors) to overcome resistance in a clinical setting. These data were obtained within the framework of the collaboration with Pr. Gilles Favre (Cancer Research Center of Toulouse).

The poster presentation supports AsiDNA™’s potential to protect healthy cells from toxicities of several anti-cancer treatments. When combined with different anti-cancer treatments (Carboplatin+/-Paclitaxel in long-term treatment, Radiotherapy, Doxorubicin, PARP inhibitors), AsiDNA™ induces its nuclear target engagement only in dividing cells, while preserving healthy non dividing cells. In addition, in certain proliferating healthy cells, AsiDNA™ induces a stop in their division or boosts their DNA repair activity, thus protecting them from the toxic effects of anti-cancer treatments. These data were obtained in in vivo and in vitro models within the framework of the collaboration with Pr. Marie Dutreix (Institut Curie).

Wael Jdey, Preclinical Lead of Onxeo, stated: “These new data accepted for presentation at the AACR 2022 complement the pre-clinical and clinical package already obtained with AsiDNA™. With its differentiated mechanism of action, AsiDNA™ has shown its ability to work in the new preclinical tumor models that are resistant to TKi’s especially Osimertinib in EGFR-mutated NSCLC models. We are excited to present these data to the scientific community and are looking forward to initiating the next steps of the AsiDNA™ development plan”.

Oral Session: MS.ET03.01 – Elucidating Disease Biology and Drug Resistance Mechanisms
Date/ Time: April 10, 2022 – 3:35 AM - 3:50 PM (U.S. Eastern Daylight Time - EDT)

To read the abstract: DNA repair-interfering molecule AsiDNA® overcomes resistance to tyrosine kinase inhibitors in lung cancer

Poster Session: PO.ET04.02 – DNA Damage Response and Repair
Date/ Time: April 12, 2022 – 9:00 AM - 12:30 PM (U.S. Eastern Daylight Time - EDT)

To read the abstract: AsiDNA® treatment protects healthy cells from anticancer treatment toxicity

Next financial press release:

• Full-year 2021 results: Thursday, April 7, 2022 (before market opening)

About Onxeo

Onxeo (Euronext Paris, NASDAQ Copenhagen: ONXEO) is a clinical-stage biotechnology company developing innovative oncology drugs targeting tumor DNA-binding functions through unique mechanisms of action in the sought-after field of DNA Damage Response (DDR). The Company is focused on bringing early-stage first-in-class or disruptive compounds from translational research to clinical proof-of-concept, a value-creating inflection point appealing to potential partners.

platON™ is Onxeo’s proprietary chemistry platform of oligonucleotides acting as decoy agonists, which generates new innovative compounds and broaden the Company’s product pipeline.

AsiDNA™, the first compound from platON™, is a highly differentiated, clinical-stage first-in-call candidate in the field of DNA damage response (DDR) applied to oncology. Its decoy and agonist mechanism acting upstream of multiple DDR pathways results in distinctive antitumor properties, including the ability to prevent or abrogate tumor resistance to targeted therapies such as PARP inhibitors and strong synergy with tumor DNA-damaging agents such as radio-chemotherapy. AsiDNA™ is currently in combination clinical trials in difficult-to-treat solid tumors.

OX401 is a new drug candidate from platON™, designed to be a next-generation PARP inhibitor acting on both the DNA Damage Response and the activation of immune response, without inducing resistance. OX401 is currently being optimized and is 0undergoing preclinical proof-of-concept studies, alone and in combination with immunotherapies.

For further information, please visit www.onxeo.com.

Forward looking statements
This communication expressly or implicitly contains certain forward-looking statements concerning Onxeo and its business. Such statements involve certain known and unknown risks, uncertainties and other factors, which could cause the actual results, financial condition, performance or achievements of Onxeo to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Onxeo is providing this communication as of this date and does not undertake to update any forward-looking statements contained herein as a result of new information, future events or otherwise. For a discussion of risks and uncertainties which could cause actual results, financial condition, performance or achievements of Onxeo to differ from those contained in the forward-looking statements, please refer to the risk factors described in the most recent Company’s registration document or in any other periodic financial report and in any other press release, which are available free of charge on the websites of the Company Group (www.onxeo.com) and/or the AMF (www.amf-france.org).

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Onxeo

Valerie Leroy,

Investor Relations

investors@onxeo.com

+33 1 45 58 76 00

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Source: Onxeo