Polyplus-Transfection and ExcellGene Enter Into a Supply Agreement for PEI-Based Transfection Reagents

STRASBOURG, France, May 11, 2011 - Polyplus-transfection SA, a privately-held company developing innovative
technologies for molecular and cellular biology, announced today that
ExcellGene SA, a privately held company providing rapid and low-cost
solutions for protein manufacturing and process development based on
mammalian cells to the Pharma/Biotech industry, has signed an extended supply
agreement for Polyplus-transfection polyethylenimine (PEI) based transfection
reagents.

Polyplus-transfection will supply ExcellGene with batches of high quality
linear PEI transfection reagent which is specifically formulated and subject
to appropriate quality controls (transfection activity and microbiological
tests) that ensure reliable, safe and reproducible protein production in
medium to large scale. In addition, by purchasing PEI from
Polyplus-transfection, ExcellGene benefits from an implied license regarding
Polyplus' intellectual property rights for the use of PEI in transient and
stable transfection.

"We are truly delighted to sign a supply agreement for PEI for
transfection with ExcellGene, a recognized leader in providing process
solutions for the pharmaceutical and biotech industry in the field of
recombinant expression technologies," said Mark Bloomfield, CEO of
Polyplus-transfection. "This agreement demonstrates the superiority of
Polyplus PEI for bioproduction and the value of our intellectual property
rights and knowhow in the field of PEI-mediated nucleic acid delivery."

"Known for our highly innovative approaches in protein production from
mammalian cells we have studied extensively a large variety of DNA transfer
systems and have found Polyplus polyethylenimine of highest quality and
serving best our needs," said Dr. Maria De Jesus, Chief Operating Officer of
ExcellGene.

Prof. Florian Wurm, founder and interim CEO of ExcellGene added: "In our
highly regulated industry, the reliable sourcing of materials for any type of
manufacturing is key to the confidence we wish to establish with our clients,
since the final goal of our work is the provisioning of highest value protein
therapeutics to the treating doctor and the patient in need."

Financial terms were not disclosed.

About Polyplus-transfection SA

Polyplus-transfection SA is a biotechnology company that develops,
markets and sells innovative solutions for the in vivo, in vitro and ex vivo
delivery of nucleic acids in research, bioproduction and therapeutics.
Located close to the University of Strasbourg in Eastern France,
Polyplus-transfection has been ISO 9001-certified since 2002 and supplies its
proprietary range of reagents for the transfection of genes, oligonucleotides
and siRNA through a worldwide distributor network. Polyplus reagents are
involved in a growing number of clinical trials worldwide. In addition,
Polyplus-transfection holds a broad estate of patents and licenses including
original methods for therapeutic siRNA delivery.

For more information, please visit the Polyplus-transfection web site at:
www.polyplus-transfection.com

About ExcellGene SA

ExcellGene SA is an established, science and technology driven Service
Provider to the Pharma/Biotech industry. It pioneered innovative technologies
resolving problems of expression and manufacture of recombinant proteins from
mammalian cells. ExcellGene's technologies cover vectors, gene transfer
systems, cell hosts, screening platforms for cells and processes, scale-up
principles and bioreactors. Over hundred international client companies have
been satisfied with ExcellGene's services. Recently, ExcellGene received
approval for API production from the Swiss Regulatory Agency for its cGMP
manufacturing facility which features bioreactors of up to 250 L scale of
operation.

For more information, please visit the ExcellGene web site at
www.excellgene.com

    For further information, please contact:
    Andrew Lloyd & Associates
    Andrew Lloyd / Neil Hunter
    Tel: +44(0)1273-675100
    allo@ala.com / neil@ala.com

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