Trophos SA and CHDI, Inc. extend partnership to develop …

       Trophos SA and CHDI, Inc. extend partnership to develop
   promising compounds in models relevant to Huntington disease

    Neurodegenerative disease specialist and Huntington disease organization continue
                         collaboration to develop new therapies

Marseille, September 21, 2006 - Trophos SA, a biopharmaceutical company specializing in the
discovery and development of drugs for neurodegenerative diseases and CHDI, Inc. (CHDI), a
non-profit organization that supports translational research aimed at finding treatments that
prevent or slow the progression of Huntington disease (HD), announced today the extension of a
strategic collaboration to discover and develop drugs for Huntington disease.

The development program builds upon a successful collaboration to identify compounds that
confer a survival benefit on primary striatal neurons subjected to Huntington-mediated toxicity
in assays enabled by the proprietary screening platform developed at Trophos. Lose of striatal
neurons is considered an important factor in the pathogenesis of Huntington disease. During the
collaboration, Trophos and CHDI will seek to optimize the most promising compounds from
three chemical series to enable preclinical testing in models relevant to HD pathology. Trophos
retains the right to develop and commercialize the clinical candidates arising from the program
as therapeutics for HD.

"Trophos' primary neuronal cell screening platform represents an important part of CHDI's
portfolio. We look forward to our continued partnership with Trophos to explore the progression
of compounds as they are identified," said Robert Pacifici, CSO at CHDI

"We are pleased that CHDI has chosen to continue to support the chemical optimization and
pharmacological profiling of these three families of molecules identified using the proprietary
neuronal cell screening platform developed at Trophos," said Rebecca Pruss, CSO at Trophos.
"Access to the network of academic and clinical Huntington disease experts, along with the
enabling drug development technologies CHDI has assembled, will facilitate the rapid
translation of our most promising compounds into drug candidates for future clinical
development."
About Huntington disease (HD):

HD is a familial disease, passed from parent to child through a mutation in a gene. Each child of
an HD parent has a 50-50 chance of inheriting the HD gene which causes programmed
degeneration of brain cells and results in emotional disturbance, loss of intellectual faculties and
uncontrolled movements. Most people with HD develop the symptoms at midlife but in some
people onset occurs in infancy or old age. The average survival time after onset is approximately
fifteen to twenty years. It is estimated that about one in every 10,000 persons has the HD gene.
At this time, there is no way to stop or reverse the course of HD.

About Trophos: www.trophos.com

Trophos is a biopharmaceutical company developing drugs to treat neurodegenerative diseases,
including Huntington disease. These are severely debilitating, often fatal, disorders with few
effective drugs and tremendous unmet medical needs. Trophos collaborates actively with patient
associations   who    contribute   important   scientific   and      clinical   expertise   related   to
neurodegenerative diseases, as well as research funding. Trophos was founded in 1999, is based
in Marseille, France and currently has 35 employees.

About CHDI, Inc. and High Q Foundation:

CHDI Inc. and the High Q Foundation, Inc. (High Q) are non-profit organizations that share the
mission of bringing together academia, industry, governmental agencies, and other funding
organizations in the search for Huntington disease (HD) treatments.

CHDI, Inc. is pursuing a biotech approach to rapidly discover and develop drugs that prevent or
slow HD. Through collaborations with industrial and academic partners, CHDI, Inc., participates
in all aspects of drug discovery and development from high throughput screening to preclinical
development. For more information about CHDI, Inc. and its collaborative programs, please see
www.chdi-inc.org or contact Robert Pacifici (robert.pacifici@chdi-inc.org).
High Q supports HD research aimed at target identification and validation, the development and
use of animal models, drug delivery, and the search for markers of disease progression. For more
information about High Q and its support of HD research please see www.highqfoundation.org
or   contact    Ethan    Signer      (ethan.signer@highqfoundation.org)    or    Allan    Tobin
(allan.tobin@highqfoundation.org).


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