Onxeo: Validive® at the MASCC/ISOO International Symposium:

Oral Presentation of Phase II Trial Results and Meeting with Its International
Advisory Board
PARIS & COPENHAGEN, Denmark--(BUSINESS WIRE)-- Regulatory News:

Onxeo S.A. (Paris:ONXEO) (NASDAQ OMX:ONXEO) (Euronext Paris, NASDAQ Copenhagen:
ONXEO), an innovative company specializing in the development of orphan oncology
drugs, has presented Validive® (clonidine Lauriad®) Phase II clinical trial
results at the MASCC/ISOO International Symposium which took place in Copenhagen
from June 25 to June 27, 2015 and on this occasion, held a meeting of its
Advisory Board to discuss design of the Phase III clinical trial.

The annual MASCC/ISOO meeting is dedicated to supportive care in cancer and
particularly to therapeutic options to minimize symptoms and complications
associated with cancer as well as therapy-induced side effects. Validive® was
distinguished to be part of this oncololy supportive care forum with an oral
presentation of the positive final results of its Phase II clinical trial. These
final data confirm the product’s favorable safety profile and efficacy in
reducing severe oral mucositis in patients with head and neck cancer receiving
chemoradiation therapy. These positive results provide the basis for a Phase III
trial to further evaluate the efficacy of Validive®, which Onxeo plans to
initiate by end 2015/early 2016.

This event was therefore the designated opportunity for Onxeo to bring together
some members of its international Advisory Board* dedicated to oral mucositis
and to the associated clinical development program with Validive®. At this point
in the product’s development stage, the discussion was focused on the Board’s
recommendations on the Phase III trial design, especially in terms of
indication, dosage, population and clinical endpoints, based on the phase II
final results.

“We were very happy to share these positive results with the medical community,
and in particular with those who need to provide their patients with a new,
attractive therapeutic option to prevent severe oral mucositis, a severe
condition induced by chemoradiation therapy for which no preventive treatment is
currently available. Clonidine Lauriad represents a very promising product and
its mucoadhesive formulation makes it especially well adapted to treat oral
mucositis ”, comments Pr René-Jean Bensadoun, principal investigator of the
Phase II clinical trial.

“The MASCC conference has been a great opportunity for us to meet with our key
advisors to discuss further palnds for the development of Validive® further. The
board has shown again great enthousiasm around Validive® as a potential
treatment of severe oral mucositis and we would like to thank them for their
support and accurate advice as international experts of Oral Mucositis,
regarding our phase III plan. ”, added Graham Dixon, CSO Head of R&D of Onxeo.

*This multidisciplinary Advisory Board is composed of internationally recognized
European and American experts, in the fields of oral mucositis and oral
medicine, oncology and radiotherapy: Drs René-Jean Bensadoun (Nice, France),
Paolo Bossi (Milan, Italy), Joel Epstein (Duarte, US), Jorge Giralt Lopez del
Segredo (Barcelona, Spain), Michael Henke (Freiburg, Germany), Rajesh Lalla
(Farmington, US), Stephen Sonis (Boston, US) and Yungan Tao (Villejuif, France).
Its purpose is to provide advice and input on development strategy and medical
positioning of Validive® in oral mucositis.

About severe oral mucositis
Severe oral mucositis is a particularly invalidating pathology occurring in more
than 60% of patients treated with radio/chemotherapy for head and neck cancer
and has currently no validated curative or preventive treatment. It may induce
intense oral pain and eating disability requiring enteral or parenteral
nutritional support. Thirty percent of patients need to be hospitalized as a
result and symptoms can force patients to stop treatment for an undefined period
thus reducing treatment efficacy.

About MASCC/ISOO
« Multinational Association of Supportive Care in Cancer » (MASCC) is an
international, multidisciplinary organization dedicated to supportive care for
patients with cancer. In 1998 MASCC joined forces with the « International
Society of Oral Oncology » (ISOO), an organization that addresses the management
of complications arising in oral tissues secondary to cancer and its treatments.
The MASCC/ISOO Annual Meeting on Supportive Care in Cancer is designed to
educate and inform an international audience of healthcare professionals on ways
to minimize symptoms and complications associated with cancer as well as therapy
-induced side effects. This meeting is intended for physicians, nurses,
dentists, oral surgeons, dental hygienists, pharmacists, social workers,
nutritionists, and other healthcare providers involved in the care of cancer
patients.

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
final results
Beleodaq® (belinostat): registered in the US in 2nd line treatment of 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
Onxeo
Judith Greciet, CEO
j.greciet@onxeo.com
Nicolas Fellmann, CFO
n.fellmann@onxeo.com
+33 1 45 58 76 00
or
Caroline Carmagnol and Florence Portejoie
onxeo@alizerp.com
+33 6 64 18 99 59 / +33 1 44 54 36 66