BioMarin Initiates Phase 1 Clinical Study of PEG-PAL in PKU

NOVATO, Calif., May 20 /PRNewswire-FirstCall/ -- BioMarin Pharmaceutical
Inc. (Nasdaq and SWX: BMRN) today announced that the first patient has
initiated treatment in the Phase 1 clinical study of PEG-PAL (PEGylated
recombinant phenylalanine ammonia lyase) for the treatment of phenylketonuria
(PKU). The study is expected to conclude enrollment in the fourth quarter of
2008.
"We are dedicated to serving the PKU community and hope to address the
entire spectrum of PKU patients between PEG-PAL and Kuvan. We believe PEG-PAL
holds tremendous potential to bring blood Phe down to normal levels and may
help patients who either do not respond to Kuvan or who wish to reduce blood
Phe levels beyond what is possible with Kuvan," said Jean-Jacques Bienaime,
Chief Executive Officer of BioMarin. "Positive preclinical data shows
sustained decreases in blood Phe levels in PKU mice without any notable safety
concerns and we hope to see the same results in humans."
The Phase 1 clinical trial is an open-label, multi-center study to be
conducted in approximately 35 PKU patients in a series of seven dose-
escalating cohorts ranging from 0.001 to 1.0 mg/kg, with each cohort receiving
a single dose, and a 6-week follow-up period.
The primary objective of the study is to assess the safety and
tolerability of single, subcutaneous injections of PEG-PAL in subjects with
PKU. The secondary objectives of the study are to evaluate the
pharmacokinetics of single, subcutaneous injections of PEG-PAL administered at
escalating doses and to evaluate the effect of PEG-PAL on blood Phe
concentrations in subjects with PKU.
About PEG-PAL
PEG-PAL (PEGylated recombinant phenylalanine ammonia lyase) is an
investigational enzyme substitution therapy for the treatment of PKU.
Pharmacology studies conducted in the PKU mouse model demonstrated that weekly
subcutaneous administrations of PEG-PAL resulted in a significant and stable
decrease of plasma phenylalanine. BioMarin estimates that PEG-PAL could be a
potential treatment option for a significant portion of the PKU population.
About BioMarin
BioMarin develops and commercializes innovative biopharmaceuticals for
serious diseases and medical conditions. The company's product portfolio
comprises three approved products and multiple clinical and preclinical
product candidates. Approved products include Naglazyme(R) (galsulfase) for
mucopolysaccharidosis VI (MPS VI), a product wholly developed and
commercialized by BioMarin; Aldurazyme(R) (laronidase) for
mucopolysaccharidosis I (MPS I), a product which BioMarin developed through a
50/50 joint venture with Genzyme Corporation; and Kuvan(R) (sapropterin
dihydrochloride) Tablets, a product for the treatment of phenylketonuria
(PKU), developed in partnership with Merck Serono, a division of Merck KGaA of
Darmstadt, Germany. Other product candidates include 6R-BH4 for cardiovascular
indications, which is currently in Phase 2 clinical development for the
treatment of peripheral arterial disease and sickle cell disease, and PEG-PAL
(PEGylated recombinant phenylalanine ammonia lyase), which is currently in
Phase 1 clinical development for the treatment of PKU. For additional
information, please visit http://www.BMRN.com. Information on BioMarin's
website is not incorporated by reference into this press release.
Forward-Looking Statement
This press release contains forward-looking statements about the business
prospects of BioMarin Pharmaceutical Inc., including, without limitation,
statements about: the development of its product candidate PEG-PAL, and
expectations regarding filings with regulatory agencies. These forward-looking
statements are predictions and involve risks and uncertainties such that
actual results may differ materially from these statements. These risks and
uncertainties include, among others: the results of current and planned
clinical trials related to PEG-PAL; the content and timing of decisions by the
U.S. Food and Drug Administration and other regulatory agencies, particularly
with respect to PEG-PAL, and those factors detailed in BioMarin's filings with
the Securities and Exchange Commission, including, without limitation, the
factors contained under the caption "Risk Factors" in BioMarin's 2007 Annual
Report on Form 10-K. Stockholders are urged not to place undue reliance on
forward-looking statements, which speak only as of the date hereof. BioMarin
is under no obligation, and expressly disclaims any obligation to update or
alter any forward-looking statement, whether as a result of new information,
future events or otherwise.
BioMarin(R), Naglazyme(R) and Kuvan(R) are a registered trademarks of
BioMarin Pharmaceutical Inc.
Aldurazyme(R) is a registered trademark of BioMarin/Genzyme LLC.

Contacts:

Investors Media
Eugenia Shen Susan Berg
BioMarin Pharmaceutical Inc. BioMarin Pharmaceutical Inc.
(415) 506-6570 (415) 506-6594

SOURCE BioMarin Pharmaceutical Inc.

Investors, Eugenia Shen, +1-415-506-6570, or Media, Susan Berg,
+1-415-506-6594, both of BioMarin Pharmaceutical Inc.