Onxeo

AGM Information • May 20, 2015

Onxeo's Combined General Meeting of Shareholders

Paris (France), Copenhagen (Denmark), May 20, 2015 – Onxeo S.A. (Euronext Paris, NASDAQ Copenhagen: ONXEO), an innovative company specializing in the development of orphan oncology drugs, today announced that the General Meeting, held at the company's headquarters in Paris, France on May 20, 2015, adopted all of the resolutions recommended by the Board of Directors.

Please be advised that the voting results of the Combined General Meeting are available on our website www.onxeo.com, in the section "Investors/General meetings".

About Onxeo

Onxeo has the vision to become a global leader and pioneer in oncology, with a focus on orphan or rare cancers, through developing innovative therapeutic alternatives designed to "make the difference". The Onxeo team is determined to develop innovative medicines that provide patients with hope and significantly improve their lives.

Key orphan oncology products at the advanced development stage are:

Livatag® (doxorubicin Transdrug™): Phase III in hepatocellular carcinoma Validive® (clonidine Lauriad® ): Phase II in severe oral mucositis: Positive preliminary top-line results Beleodaq® (belinostat): registered in the US in peripheral T-cell lymphoma For more information, visit the website www.onxeo.com

Disclaimer

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 ("Facteurs de Risque") section of the 2014 Reference Document filed with the AMF on April 14, 2015, which is available on the AMF website (http://www.amf-france.org) or on the company's website (www.onxeo.com).

Contacts :

Judith Greciet, CEO j.greciet@onxeo.com Nicolas Fellmann, CFO n.fellmann@onxeo.com +33 1 45 58 76 00

Caroline Carmagnol / Sophie Colin – Alize RP onxeo@alizerp.com +33 6 64 18 99 59 / +33 1 44 54 36 62

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