Cellectis Sues Precision BioSciences for Infringement of its Patents Concerning Meganuclease Technology

Biocitech Park, Romainville, France (ots/PRNewswire) -
Cellectis SA (NYSE: ALCLS), a world leader in rational genome
engineering, has announced today that it filed a patent infringement
lawsuit against Precision BioSciences, Inc. in the United States
District Court for the Eastern District of North Carolina. The
lawsuit seeks a declaration that, by making and selling certain
meganucleases, Precision BioSciences infringes two Cellectis patents
relating to its proprietary meganuclease recombination systems. The
Precision Biosciences' meganucleases at issue are intended to target
site-specific DNA breaks and effect a desired genome modification in
a given transgenic organism, such as a plant. The lawsuit seeks both
monetary damages for infringement, as well as a permanent injunction
preventing Precision BioSciences from any further making, using or
selling of such meganucleases. "We take our intellectual property
rights very seriously and intend to vigorously pursue this patent
infringement case," said Dr. Andre Choulika, CEO and co-founder of
Cellectis SA., and the man who participated in coining the term
"meganuclease."

Since its creation in January 2000 and throughout its
development, Cellectis has made special efforts to protect new
discoveries made by its research team as well as those of its
partner, the world-renowned Institut Pasteur. Cellectis currently
owns the exclusive rights to over 35 issued patents and 113 pending
patent applications. Most of these patents are based on Cellectis'
fully integrated genome engineering system referred to as its
Meganuclease Recombination Systems (MRSs). These systems offer
natural, efficient, precise and flexible genome surgery with several
applications, among others, in the therapeutic area and in the plant
science field.

About Cellectis

Cellectis SA (http://www.cellectis.com) is a world-leading
company in genome engineering and genome surgery. The company is
focused on developing and producing custom meganucleases for in vivo
DNA surgery and also provides new tools for rational reverse genetics
and targeted recombination. Cellectis' products induce unique,
site-directed, double-strand DNA breaks in living cell and can be
used in a wide range of biotechnological and therapeutic
applications.

A strong Patent portfolio

Cellectis holds exclusive rights to 148 patents and patent
applications providing the company with a strong position in the
field of homologous recombination (3 issued US patents) and
meganucleases and uses thereof (18 issued US patents) both
naturally-occurring and with engineered specificity. A significant
part of this patent portfolio has been exclusively licensed by
Institut Pasteur, which spun off the company in 2000.

Institut Pasteur, thanks to its work with pioneering groups in
the filed, has a long history in the exploitation of methods of
homologous recombination, a major scientific breakthrough (Nobel
Prize 2007) and is today the assignee of cornerstone patents from the
late 80's. Finally the team, which discovered meganucleases and
published founding works on the I-SceI homing endonucleases leading
to the constitution of the Cellectis proprietary patent portfolio, is
from Institut Pasteur.

A strong scientific background

Teams involved in the discovery of meganucleases at Institut
Pasteur and Cellectis have published tens of cornerstone publications
in prestigious peer-review papers such as Cell, Nature, Science,
PNAS, JBC or JMB. For the sole year 2007, Cellectis has published 5
important scientific publications in peer-review journals and 2
papers since the beginning of 2008.

A technology that delivers

Cellectis currently holds a portfolio of 18 meganucleases with
modified specificity, deriving from the I-CreI meganuclease with
applications in:

- Healthcare, Therapeutics - major indications are severe innate
genetic diseases, DNA virus infectious diseases, transplantation and
Cancer

- Agricultural biotechnology - major targets are seed
improvements, biofuels and biofibers

- BioProduction - major indications are cell line and
recombinant protein improvements

- BioTools - a major indication is the development of research
kits for pharmacogenomic studies and in particular drug screening

A partner oriented strategy

The company has signed 48 partnerships with pharmaceutical
companies (Astra-Zeneca, GSK, Shire), agricultural biotechnology
groups (Limagrain, Bayer, BASF, DuPont-Pioneer HiBred) and biotech
companies (Genentech, Transgenics, Lexicon). Cellectis contributes to
over 20 academic partnerships including Institut Gustave Roussy
cancer research centre, Paris Childrens Hospital (France), Boston
Childrens Hospital or Harvard Gene Therapy Initiative (USA).

Financing

The company raised above EUR24m in an IPO on NYSE Euronext
Alternext (February 2007) to increase its meganucleases production
capacity to 20 products a year by the end of 2008. To date the
company has raised over EUR40m both in private and public rounds.

Cellectis is listed on the NYSE Euronext Alternext market (ticker
code: ALCLS). For more information on Cellectis, visit our web site:
http://www.cellectis.com.

Cellectis' Forward-Looking Statements

This communication expressly or implicitly contains certain
forward-looking statements concerning Cellectis SA 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
Cellectis SA to be materially different from any future results,
performance or achievements expressed or implied by such
forward-looking statements. Cellectis SA 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 Cellectis SA to differ from
those contained in the forward-looking statements please refer to the
Risk Factors (Facteurs de Risque) section of the prospectus approved
by the French Autorite des Marches Financiers ("AMF") on January
22nd, 2007 under visa number 07-023, available on the websites of the
AMF ( http://www.amf-france.org) and Cellectis
(http://www.cellectis.com)

ots Originaltext: Cellectis SA
Im Internet recherchierbar: http://www.presseportal.de

Contact:
For further information please contact: Cellectis SA, Andre Choulika,
PhD., Chief Executive Officer, +33-(0)1-41-83-99-00,
mail@cellectis.com. Alize RP, Caroline Carmagnol,
caroline@alizerp.com, +33-(0)-6-64-18-99-59