Onxeo Receives EPO Intent-to-Grant Notice for Key AsiDNA™ Patent, Extending IP Protection in Europe Until 2031

Regulatory News:

Onxeo S.A. (Euronext Paris, NASDAQ Copenhagen: ONXEO - FR0010095596), ("Onxeo” or the "Company”), a biotechnology company specializing in the development of innovative drugs in oncology, in particular against rare or resistant cancers, today announced having received a communication from the European Patent Office (EPO) informing the Company of its intent to grant a new patent covering AsiDNA™, Onxeo’s first-in-class DNA break repair inhibitor candidate in all countries of the European Union (EU).

This new patent significantly strengthens the Company’s intellectual property portfolio by protecting several conjugated nucleic acid molecules including AsiDNA™ as well as the pharmaceutical compositions and their therapeutic uses, especially for treating cancer, standalone and in combination with a DNA-damaging antitumoral agent (such as radiotherapy, chemotherapy or other tumor DNA damage-inducing agents).

This European patent has a term expiring in mid-2031. This term could be further extended to mid-2036 through a supplementary protection certificate (SPC).

The similar US patent was granted in July 2016.

"This patent covering the composition of matter provides the strongest protection possible in the field of Intellectual Property and is a key component of the value of AsiDNA™. This enlarged patent protection is key in a year when the company accelerates clinical development of AsiDNA™ to reach the next meaningful value inflexion points in the coming months,” said Judith Greciet, Chief Executive Officer of Onxeo.

AsiDNA^TM, a first-in-class DNA break repair inhibitor with blockbuster potential

The "decoy” mechanism of AsiDNA™, called signal-interfering DNA (siDNA) is genuinely unlike any other: it uses small "broken” double-strand DNA molecules to trigger a false DNA damage signal that hides the signal emitted by true DNA lesions on tumor cells, whether induced by spontaneous mutations in genetically unstable cancer cells or by anti-cancer treatments. The repair enzymes are distracted by this false DNA damage signal, and are no longer recruited at the true damage sites. Tumor cells will thus die from continuing to divide with damaged DNA. Another differentiated feature of AsiDNA™ is that - unlike other DNA damage response agents that act on a specific repair enzyme, such as PARP inhibitors - AsiDNA™ is not limited to a single DNA repair pathway but impairs multiple pathways, hence bypassing the usual tumors resistance to treatments. In addition, AsiDNA does not seem to be damaging healthy cells or tissues in any of our studies so far, including in its first phase I in combination with radiotherapy in metastatic melanoma.

The technology has already demonstrated its ability to increase the efficacy of radiotherapy, radiofrequency ablation, chemotherapy, PARP inhibitors or HDAC inhibitors in a variety of preclinical animal models, positioning it as a promising candidate for both mono- and combination therapies.

AsiDNA^TM is currently being developed for systemic (IV) administration in solid tumors, with the first patients treated in a dose-escalation phase 1 study expected in the first quarter of 2018.

About Onxeo

Onxeo (Euronext Paris, NASDAQ Copenhagen: ONXEO) is a French biotechnology company developing innovative oncology drugs based on DNA-targeting and epigenetics, two of the most sought-after mechanisms of action in cancer treatment today. The Company is focused on bringing early-stage first-in-class or disruptive compounds (proprietary, acquired or in-licensed) from translational research to clinical proof-of-concept, a value-creating inflection point appealing to potential partners.

Onxeo’s R&D pipeline includes belinostat, an HDAC inhibitor (epigenetics) currently being developed in oral form to be used in combination with other anti-cancer agents for liquid or solid tumors. Belinostat is already conditionally FDA-approved in the US as a 2^nd line treatment for patients with peripheral T cell lymphoma and marketed in the US by Onxeo’s partner, Spectrum Pharmaceuticals, under the name Beleodaq® (belinostat IV form).

Onxeo is also developing AsiDNA™, a first-in-class DNA break repair inhibitor based on a unique decoy mechanism. AsiDNA™ has already successfully completed a Phase I trial in metastatic melanoma via local administration, and is currently being developed for systemic (IV) administration in solid tumors.

AsiDNA™ is the first compound generated from platON™, the Company’s proprietary chemistry platform of decoy oligonucleotides based on three components, a sequence of double strand oligonucleotides, a linker and a cellular uptake facilitator. PlatON™ will continue to generate new compounds that will broaden Onxeo’s pipeline.

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 section 5.5.1.4 "Risk Factors” ("Facteurs de Risque") of the 2016 reference document filed with the Autorité des marchés financiers on April 24, 2017 under number D.17-0423, which is available on the Autorité des marchés financiers website (www.amf-france.org) or on the Company’s website (www.onxeo.com).

View source version on businesswire.com: http://www.businesswire.com/news/home/20180125006134/en/