Shire Presents Positive Data for Patients With Type 1 Gaucher Disease Who Switched to VPRIV(TM)

Also Reported are Results of Retrospective Analysis of Phase I/II Study, Showing Success in Reaching Therapeutic Goals within 4 Years of Initiation of Treatment

CAMBRIDGE, Massachusetts, March 25, 2010 - Shire plc (LSE: SHP, NASDAQ: SHPGY), the global specialty
biopharmaceutical company, today presented positive data from a Phase III
clinical trial (TKT-034) designed to evaluate the safety of switching to
VPRIV (velaglucerase alfa for injection), from imiglucerase, as well as an
interim analysis of safety data from an ongoing multicenter open-label
treatment protocol (HGT-GCB-058) implemented to provide VPRIV to patients
affected by the continuing shortage of imiglucerase. A post-hoc analysis of
Phase I/II data on therapeutic goal attainment was also presented at the 2010
American College of Medical Genetics Annual Clinical Genetics Meeting in
Albuquerque, New Mexico. These data add to the growing body of clinical
evidence which support the use of VPRIV in patients both transitioning from
imiglucerase or who are treatment naive.

Adult and pediatric patients with Type 1 Gaucher disease were switched
from imiglucerase (15-60 U/kg every other week) to the same number of units
of VPRIV in the Phase III switch study (40 patients) and the ongoing US
treatment protocol (>150 patients). In study TKT-034, no patients developed
IgG antibodies to VPRIV, including 3 patients who tested positive for
anti-imiglucerase antibodies at screening. In addition, hemoglobin
concentration, platelet counts, and liver and spleen volumes remained stable
over the course of the one year study, demonstrating safety and maintenance
of efficacy over this time frame. One patient in the Phase III trial
discontinued due to a serious hypersensitivity reaction and the most common
side effects reported in the two studies were infusion-related reactions.

"Results from the Phase III study provide important information regarding
the safety and sustained efficacy of VPRIV for patients with Type 1 Gaucher
disease who were previously on imiglucerase and should help inform treatment
decisions during and after the imiglucerase supply shortage," said Dr.
Gregory Grabowski, Director of the Division of Human Genetics, Cincinnati
Children's Hospital Medical Center and Principal Investigator of the 034
study. "These data confirm what many physicians have experienced."

A post hoc analysis from a third study, TKT-025EXT, designed to examine
attainment of long-term therapeutic goals in 8 patients with Type 1 Gaucher
disease treated with velaglucerase alfa, was also presented at the meeting.
The initial dose of 60 U/kg was lowered to 30 U/kg after patients achieved at
least 2 of 4 predefined therapeutic goals following 1 year of treatment.
Clinically meaningful achievement of long-term therapeutic goals for
hemoglobin concentration, platelet counts, and liver and spleen volumes was
observed within 4 years of initiation of treatment.

Shire also reported important findings that suggested substantial
antigenic differences when antibody response to treatment with VPRIV and
imiglucerase were compared. Among the 99 patients who enrolled in the Phase
III studies the seroconversion rate was 1% (1 of 82) against VPRIV versus 23%
(4 of 17) against imiglucerase.

Velaglucerase alfa is manufactured in Shire's facility in Cambridge MA,
which was inspected and approved by the FDA for the commercial production of
VPRIV.

Study Results and Design for TKT-034, HGT-GBC-058 and TKT-025EXT

TKT-034

In this global, open-label, multicenter study, patients were enrolled in
the US (11 sites), Europe (3 sites) and Israel (1 site), and of the 41
patients enrolled, 40 received study drug. One patient discontinued due to a
serious hypersensitivity reaction and one patient discontinued at week 31 due
to a perceived lack of improvement. At the time of discontinuation, this
patient's clinical parameters were stable and consistent with those of the
entire group of patients in the study.

Hemoglobin concentration, platelet counts, and spleen and liver volume
were sustained at therapeutic levels through one year of treatment with
VPRIV, as demonstrated by pre-specified efficacy criteria for clinically
significant change:

    - Hemoglobin concentration: the mean change from baseline was -0.1 g/dL,
      with a 90 percent confidence interval of -0.3 to 0.1 g/dL, within the
      predefined efficacy criterion of plus or minus 1 g/dL.
    - Platelet counts: the percent change from baseline was +7.0%, with a 90
      percent confidence interval of 0.5 to 13.5%, within the predefined
      efficacy criterion of plus or minus 20%.
    - Spleen volume: the percent change from baseline was -5.6%, with a 90
      percent confidence interval of -10.8 to -0.4% within the predefined
      efficacy criterion of plus or minus 15%.
    - Liver volume: the percent change from baseline was -0.0%, with a 90
      percent confidence interval of -2.6 to 2.6% within the predefined
      efficacy criterion of plus or minus 15%.

Study design

The primary objective of TKT-034 was to evaluate the safety of VPRIV in
patients with Type 1 Gaucher disease who transitioned from imiglucerase to
VPRIV. The secondary objectives were to evaluate changes from baseline in
hemoglobin concentration, platelet counts, and spleen and liver volumes by
Magnetic Resource Imaging (MRI) after every other week dosing of VPRIV.

Patients over the age of two years and receiving imiglucerase at a dose
between 15 and 60 U/kg every other week for at least 30 months with no dose
change in the last 6 months were eligible, provided they had demonstrated
stable hemoglobin concentration and platelet counts. Patients were infused in
one hour with the same number of units of VPRIV as their prior imiglucerase
dose.

HGT-GCB-058

This ongoing multicenter, open-label treatment protocol was initiated at
the request of the Food and Drug Administration (FDA) to provide VPRIV to
patients who otherwise have limited or no access to imiglucerase due to a
continuing supply shortage.

Between September 1, 2009 and January 31, 2010, more than 150 patients in
the US enrolled into HGT-GCB-058 and received at least one infusion of VPRIV.
Of these, 3 were treatment naive and the rest were previously treated with
imiglucerase. Following the administration of the first three infusions of
VPRIV at the clinical site, patients who experienced no treatment-related
serious adverse events or infusion-related adverse events were eligible to
transition to home therapy at the discretion of the investigator. Patients
were required to return to the clinic site quarterly for observation.

An interim safety analysis of the more than 150 patients on the treatment
protocol was conducted. Among those patients previously treated with
imiglucerase, a total of 18% experienced a treatment emergent adverse event
that was possibly or probably related to the study drug. The most commonly
observed treatment emergent adverse events among switch patients included at
least one infusion-related reaction, nasopharyngitis, nausea, fatigue,
headache, dizziness and influenza. Approximately 1% of patients experienced a
severe adverse event that was considered to be possibly or probably related
to the study drug.

TKT-025EXT: Study Results and Design of Therapeutic Goal Analysis

This post-hoc analysis of data from the Phase I/II and extension trial of
velaglucerase alfa showed that clinically meaningful long-term therapeutic
goals were achieved within 4 years of initiation of velaglucerase alfa
treatment.

The efficacy parameters were evaluated against the therapeutic goals
described by Pastores et al (Seminars in Hematology, 2004) aand included
absolute and percent changes in hemoglobin levels, platelet counts, and
spleen and liver volumes as measured by MRI. Evaluation in this study was
limited to those patients who were exposed to velaglucerase alfa for a
minimum of 48 months and for whom a complete clinical data set corresponding
to the study endoints was available at baseline and annually through 48
months (8 patients, 4 male, 4 female). Patients were evaluated for the
achievement of each individual therapeutic goal. The percentage of patients
achieving each specific goal over time was determined. In addition the
percentage of patients with a complete response (achieved all 4 therapeutic
goals) over time was also evaluated.

At baseline, no patient was at goal for all 4 clinical parameters: 4 of 8
patients were at goal for hemoglobin concentration, 0 of 8 for platelet
count, 4 of 8 for liver volume, and 0 of 8 for spleen volume. After 1 year of
treatment, all patients achieved at least 2 therapeutic goals, and all
patients maintained clinical parameters for goals that were already at the
recommended targets when treatment began. All 8 patients were eligible for
and began step-wise dose reduction to velaglucerase alfa 30 U/kg EOW starting
between 12 and 18 months. By year 4 of treatment, all patients met goals for
all 4 clinical parameters; therefore, 100% achievement was observed for each
of the 4 long-term, therapeutic goals.

More about VPRIV

VPRIV (velaglucerase alfa for injection) was approved by the US FDA as a
long-term enzyme replacement therapy for adult and pediatric patients with
Type 1 Gaucher disease on February 26, 2010. A marketing application for
VPRIV has also been granted accelerated assessment by the European Medicines
Agency in the European Union (EU). Shire expects to launch VPRIV in the EU by
the end of 2010 and in other countries beginning in 2011.

VPRIV is for patients who are treatment naive as well as patients who
have been treated with imiglucerase. The most serious adverse reactions seen
with VPRIV were hypersensitivity reactions. Infusion-related reactions were
the most commonly observed adverse reactions in patients treated with VPRIV
in clinical studies. The most commonly observed symptoms of infusion-related
reactions were: headache, dizziness, low or high blood pressure, nausea,
tiredness and weakness, and fever. Generally the infusion-related reactions
were mild and, in treatment-naive patients, onset occurred mostly during the
first 6 months of treatment and tended to occur less frequently with time.
Adverse reactions more commonly seen in pediatric patients compared to those
observed in adult patients (>10% difference) include rash, upper respiratory
tract infection, prolonged activated partial thromboplastin time, and fever.

As with all therapeutic proteins, there is a potential for
immunogenicity. In the clinical studies 1 of 54 treatment-naive patients
treated with VPRIV developed IgG class antibodies. It is unknown if the
presence of IgG antibodies to VPRIV is associated with a higher risk of
infusion reactions.

Full prescribing information for VPRIV can be found at
www.VPRIV.com.

Notes to editors

SHIRE PLC

Shire's strategic goal is to become the leading specialty
biopharmaceutical company that focuses on meeting the needs of the specialist
physician. Shire focuses its business on attention deficit hyperactivity
disorder (ADHD), human genetic therapies (HGT) and gastrointestinal (GI)
diseases as well as opportunities in other therapeutic areas to the extent
they arise through acquisitions. Shire's in-licensing, merger and acquisition
efforts are focused on products in specialist markets with strong
intellectual property protection and global rights. Shire believes that a
carefully selected and balanced portfolio of products with strategically
aligned and relatively small-scale sales forces will deliver strong results.

For further information on Shire, please visit the Company's website:
www.shire.com.

"SAFE HARBOR" STATEMENT UNDER THE PRIVATE SECURITIES LITIGATION REFORM
ACT OF 1995

Statements included herein that are not historical facts are
forward-looking statements. Such forward-looking statements involve a number
of risks and uncertainties and are subject to change at any time. In the
event such risks or uncertainties materialize, the Company's results could be
materially adversely affected. The risks and uncertainties include, but are
not limited to, risks associated with: the inherent uncertainty of research,
development, approval, reimbursement, manufacturing and commercialization of
the Company's Specialty Pharmaceutical and Human Genetic Therapies products,
as well as the ability to secure and integrate new products for
commercialization and/or development; government regulation of the Company's
products; the Company's ability to manufacture its products in sufficient
quantities to meet demand; the impact of competitive therapies on the
Company's products; the Company's ability to register, maintain and enforce
patents and other intellectual property rights relating to its products; the
Company's ability to obtain and maintain government and other third-party
reimbursement for its products; and other risks and uncertainties detailed
from time to time in the Company's filings with the Securities and Exchange
Commission.

    For further information please contact:

    Investor  Relations

    Clea Rosenfeld (Rest of the World), +44-1256-894-160
    Eric Rojas (North America), +1-781-482-0999

    Media

    Jessica Mann (Rest of the World), +44-1256-894-280
    Jessica Cotrone (North America, HGT), +1-781-482-9538

For further information please contact: Investor Relations: Clea Rosenfeld (Rest of the World), +44-1256-894-160; Eric Rojas (North America), +1-781-482-0999; Media: Jessica Mann (Rest of the World), +44-1256-894-280; Jessica Cotrone (North America, HGT), +1-781-482-9538