Genzyme Receives Positive CHMP Opinion for LEMTRADA™ (alemtuzumab) in Europe

  Genzyme Receives Positive CHMP Opinion for LEMTRADA™ (alemtuzumab) in Europe

– CHMP also Recommends NAS Designation for AUBAGIO^® (teriflunomide) Following
                 Positive Opinion on Approval in March 2013 –

 – Positive Opinions Set Stage for Introduction of Two New Genzyme Therapies
                      for Multiple Sclerosis in Europe –

Business Wire

CAMBRIDGE, Mass. -- June 28, 2013

Genzyme, a Sanofi company (EURONEXT: SAN and NYSE: SNY), announced today that
the Committee for Medicinal Products for Human Use (CHMP) of the European
Medicines Agency (EMA) has issued a positive opinion for approval of LEMTRADA™
(alemtuzumab) for the treatment of adult patients with relapsing remitting
multiple sclerosis (RRMS) with active disease defined by clinical or imaging
features.

In addition, the CHMP issued a positive opinion on new active substance
designation (NAS) for AUBAGIO^® (teriflunomide). Earlier this year, the CHMP
issued a positive opinion recommending the approval of AUBAGIO for the
treatment of adult patients with relapsing remitting MS.

The European Commission (EC) is expected to render a final decision to grant
marketing authorizations for LEMTRADA and AUBAGIO in the EU in the coming
months.

“Today’s CHMP opinions set the stage for the approval of two important new
treatment options for MS patients. Treatments to-date have addressed some of
the unmet needs in MS, but still have limitations,” said David Meeker, MD,
Genzyme President and CEO. “Upon approval, physicians will have the ability to
prescribe LEMTRADA for appropriate relapsing remitting patients based on their
impressions of clinical or imaging characteristics regardless of duration of
disease or treatment history. Expectations among the MS community are high for
LEMTRADA and with today’s positive CHMP opinion we are a step closer to making
this very innovative treatment available for MS patients in Europe.”

The positive CHMP opinion for approval of LEMTRADA was based on data from the
CARE-MS I and CARE-MS II trials, in which LEMTRADA was significantly more
effective than Rebif^® (subcutaneous interferon beta-1a 44 mcg three times
weekly) at reducing relapse rates. In CARE-MS II, accumulation of disability
was significantly slowed in patients given LEMTRADA vs. Rebif, and
importantly, patients treated with LEMTRADA were significantly more likely to
experience improvement in pre-existing disability.

“Today’s announcement from Genzyme represents a key milestone in the extensive
program evaluating LEMTRADA in multiple sclerosis,” said Professor Alastair
Compston, Head of the Department of Clinical Neurosciences at the University
of Cambridge, United Kingdom. “The superior efficacy of Lemtrada vs. Rebif in
the clinical trials, which was sustained despite infrequent administration,
represents an approach to treatment that promises to reshape the future for
many people with active relapsing-remitting multiple sclerosis.”

LEMTRADA has a novel dosing and administration schedule of two annual
treatment courses. The first treatment course of LEMTRADA is administered via
intravenous infusion on five consecutive days, and the second course is
administered on three consecutive days, 12 months later.

The LEMTRADA clinical development program included two randomized Phase III
studies comparing treatment with LEMTRADA to Rebif ^ in patients with
relapsing-remitting MS who had active disease and were either new to treatment
(CARE-MS I) or who had relapsed while on prior therapy (CARE-MS II), as well
as an ongoing extension study. A large randomized Phase II study provided the
foundation for the Phase III program.

Safety results were consistent across both the CARE-MS I and CARE-MS II
studies. The most common adverse events associated with LEMTRADA were
infusion-associated reactions, including headache, rash, fever, nausea and
hives. Infections were common in both the LEMTRADA and Rebif groups.
Infections more common on LEMTRADA treatment included upper respiratory and
urinary tract infections, herpes viral infections, and influenza. Most
infusion-associated reactions and infections were mild to moderate in severity
and responded to standard treatments.

In both CARE-MS I and CARE-MS II, the incidence of serious adverse events was
similar between the two treatment arms. As previously reported, autoimmune
disorders were more frequent in patients treated with LEMTRADA, primarily
autoimmune thyroid disease which was observed in an estimated 36% of patients
during extended follow-up. Immune thrombocytopenia (ITP) developed in 1.4
percent of LEMTRADA-treated patients through extended follow-up and 0.3%
developed glomerulonephritis. Autoimmune disorders were detected soon after
onset through a monitoring program, and were generally managed using standard
treatments.

A comprehensive risk management program has been proposed to support early
detection and management of adverse events.

In the U.S. the FDA has accepted for review the company’s supplemental
Biologics License Application (sBLA) file seeking approval of LEMTRADA
(alemtuzumab) for the treatment of relapsing multiple sclerosis (RMS). FDA
recently extended the review cycle for LEMTRADA^TM by three months; no
additional clinical studies have been requested, therefore FDA action on the
application is expected in late 2013.

About LEMTRADA™ (alemtuzumab)
Alemtuzumab is a monoclonal antibody that selectively targets CD52, a protein
abundant on T and B cells. Treatment with alemtuzumab results in the depletion
of circulating T and B cells thought to be responsible for the damaging
inflammatory process in MS. Alemtuzumab has minimal impact on other immune
cells. The acute anti-inflammatory effect of alemtuzumab is immediately
followed by the onset of a distinctive pattern of T and B cell repopulation
that continues over time, rebalancing the immune system in a way that
potentially reduces MS disease activity.

Genzyme holds the worldwide rights to alemtuzumab and has primary
responsibility for its development and commercialization in multiple
sclerosis. Bayer HealthCare retains an option to co-promote alemtuzumab in
multiple sclerosis. Bayer HealthCare has notified Genzyme of its intention to
co-promote under this option. Upon regulatory approval and commercialization,
Bayer would receive contingent payments based on sales revenue.

LEMTRADA is the proprietary name submitted to health authorities for the
company’s investigational multiple sclerosis agent alemtuzumab.

About AUBAGIO® (teriflunomide)
AUBAGIO is an immunomodulator with anti-inflammatory properties. Although the
exact mechanism of action for AUBAGIO is not fully understood, it may involve
a reduction in the number of activated lymphocytes in the central nervous
system (CNS).

U.S. Indications and Usage

AUBAGIO (teriflunomide) is a once-daily, oral treatment indicated in the U.S.
for patients with relapsing forms of multiple sclerosis (MS). AUBAGIO 14 mg
has shown significant efficacy across key measures of MS disease activity,
including reducing relapses, slowing the progression of physical disability,
and reducing the number of brain lesions as detected by MRI. AUBAGIO 7mg has
shown significant efficacy in reducing relapses and reducing the number of
brain lesions as detected by MRI.

Important Safety Information About AUBAGIO

The AUBAGIO U.S. label includes a boxed warning citing the risk of
hepatotoxicity and, teratogenicity (based on animal data).

In MS clinical studies with AUBAGIO, the incidence of serious adverse events
were similar among AUBAGIO and placebo-treated patients. The most common
adverse events associated with AUBAGIO in MS patients included increased ALT
levels, alopecia, diarrhea, influenza, nausea and paresthesia. Teriflunomide
is the principal active metabolite of leflunomide, which is indicated in the
U.S. and Europe for the treatment of rheumatoid arthritis. Severe liver injury
including fatal liver failure has been reported in patients treated with
leflunomide.

Leflunomide has an estimated 2.1 million patient years of exposure in
rheumatoid arthritis globally since its launch.

AUBAGIO is contraindicated in pregnant women and women of childbearing
potential who are not using reliable contraception.

AUBAGIO is supported by a robust clinical program with more than 5,000 trial
participants in 36 countries and is amongst the largest of any MS therapy.
Some patients in extension trials have been treated for up to 10 years. The EU
AUBAGIO submission includes efficacy data from the TOWER (Teriflunomide Oral
in people With relapsing remitting multiplE scleRosis) and TEMSO
(TEriflunomide Multiple Sclerosis Oral) trials.

For full prescribing information and more information about AUBAGIO, please
visit www.genzyme.com.

About Genzyme, a Sanofi Company
Genzyme has pioneered the development and delivery of transformative therapies
for patients affected by rare and debilitating diseases for over 30 years. We
accomplish our goals through world-class research and with the compassion and
commitment of our employees. With a focus on rare diseases and multiple
sclerosis, we are dedicated to making a positive impact on the lives of the
patients and families we serve. That goal guides and inspires us every day.
Genzyme’s portfolio of transformative therapies, which are marketed in
countries around the world, represents groundbreaking and life-saving advances
in medicine. As a Sanofi company, Genzyme benefits from the reach and
resources of one of the world’s largest pharmaceutical companies, with a
shared commitment to improving the lives of patients. Learn more at
www.genzyme.com.

Genzyme^® is the registered trademark of Genzyme Corporation. All rights
reserved.

Rebif^® is a registered trademark of EMD Serono, Inc. or affiliates.

About Sanofi
Sanofi, an integrated global healthcare leader, discovers, develops and
distributes therapeutic solutions focused on patients’ needs. Sanofi has core
strengths in the field of healthcare with seven growth platforms: diabetes
solutions, human vaccines, innovative drugs, consumer healthcare, emerging
markets, animal health and the new Genzyme. Sanofi is listed in Paris
(EURONEXT: SAN) and in New York (NYSE: SNY).

About Bayer HealthCare
The Bayer Group is a global enterprise with core competencies in the fields of
health care, agriculture and high-tech materials. Bayer HealthCare, a subgroup
of Bayer AG with annual sales of EUR 18.6 billion (2012), is one of the
world’s leading, innovative companies in the healthcare and medical products
industry and is based in Leverkusen, Germany. The company combines the global
activities of the Animal Health, Consumer Care, Medical Care and
Pharmaceuticals divisions. Bayer HealthCare’s aim is to discover, develop,
manufacture and market products that will improve human and animal health
worldwide. Bayer HealthCare has a global workforce of 55,300 employees (Dec
31, 2012) and is represented in more than 100 countries. More information at
www.healthcare.bayer.com.

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or
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