Sanofi and Regeneron Announce Publication of Positive Phase 2a Results of Dupilumab in Asthma in the New England Journal of

PR Newswire/Les Echos/ 
PRESS RELEASE 
Sanofi and Regeneron Announce Publication of Positive Phase 2a Results of 
     Dupilumab in Asthma in the New England Journal of Medicine 
-- Phase 2a study of the IL-4R alpha inhibitor, dupilumab, demonstrated 87%
reduction in risk of asthma exacerbations in moderate-to-severe asthma patients 
                        with elevated eosinophils - 
Paris, France, and Tarrytown, NY, May 21, 2013 -- Sanofi (EURONEXT: SAN and
NYSE: SNY) and Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced
that the New England Journal of Medicine published online the positive Phase 2a
study results of dupilumab (SAR231893/REGN668) in patients with
moderate-to-severe allergic asthma. Dupilumab is an investigational monoclonal
antibody targeting the alpha subunit of the interleukin 4 receptor (IL-4R
alpha), which modulates signaling of both IL-4 and IL-13, drivers of Th2 (Type 2
helper T cell) immune response. The study results will also be presented today
at a late-breaking clinical trials session at the American Thoracic Society 2013
International Conference. 
The proof-of-concept study enrolled 104 patients with moderate-to-severe,
persistent asthma that was not well controlled with inhaled glucocorticosteroids
(ICS) and long-acting beta agonist (LABA) therapy, and who had elevated blood or
sputum eosinophils (immune cells used as a marker of Th2 asthma in this study). 
The primary objective of the trial was to assess the effect of dupilumab, dosed
subcutaneously, weekly at 300 milligrams (mg) for twelve weeks. Patients were
treated with dupilumab (N=52) or placebo (N=52) on top of ICS and LABA therapy
for the first four weeks of the study. The LABA was withdrawn at week four and
the ICS was tapered to withdrawal between weeks six and nine. Patients were
treated for 12 weeks or until they experienced a protocol-defined asthma
exacerbation, the primary endpoint of the study. Twenty-three (23) patients
(44.2%) receiving placebo experienced an asthma exacerbation compared to three
patients (5.8%) receiving dupilumab, resulting in an 87% reduction in the
incidence of asthma exacerbations for the dupilumab arm compared to placebo
(p<0.0001). 
Clinically meaningful and statistically significant improvements were observed
for lung function and other asthma control parameters, such as forced expiratory
volume over one second (FEV1) (difference from baseline to week 12 between
dupilumab and placebo of 0.27 L, p<0.001). 
Treatment-emergent adverse events (AEs) were reported by a similar proportion of
patients in both groups (76.9% placebo; 80.8% dupilumab). AEs were generally
non-specific and of mild-to- moderate intensity. The most common AEs for placebo
and dupilumab were injection-site reaction (9.6% and 28.8%), nasopharyngitis
(3.8% and 13.5%), upper respiratory tract infection (17.3% and 13.5%), headache
(5.8% and 11.5%) and nausea (1.9% and 7.7%). 
"Despite existing therapies, a significant number of patients with
moderate-to-severe, persistent allergic asthma are not optimally controlled,
which puts them at risk of poor clinical outcomes. These patients contribute to
the significant economic burden of asthma," said Sally Wenzel, M.D., Professor
of Medicine and Director of the Asthma Institute at the University of Pittsburgh
and lead investigator of this trial. "These encouraging data support the
potential role of IL-4/IL-13 blockade in an important subset of asthma patients
and warrant continued clinical investigation." 
"These positive Phase 2 results are very encouraging. Dupilumab is the first
monoclonal antibody that demonstrated clinically meaningful activity by blocking
the IL-4R alpha subunit and consequently, both IL-4 and IL-13 signaling. These
cytokines, drivers of Th2 response, are directly involved in the pathogenesis of
asthma. Dupilumab significantly reduced exacerbations and daily symptoms in this
study and improved pulmonary function," said Gianluca Pirozzi, M.D., Ph.D.,
Global Project Head Dupilumab, Sanofi. "We are eager to move forward with the
clinical development program for dupilumab." 
These data will be presented by Dr. Sally Wenzel this morning at the American
Thoracic Society 2013 International Conference in a presentation entitled,
"Efficacy and safety of SAR231893/REGN668 in patients with moderate-to-severe,
persistent asthma and elevated eosinophil levels." 
About IL-4R and the IL-4/IL-13 Pathway
Atopic dermatitis and some types of asthma are characterized by the induction of
a specific type of an immune response that is driven by a subset of immune cells
called Type 2 helper T cells, or Th2 cells. IL-4 and IL-13 are key cytokines
that are required for the initiation and maintenance of this Th2 immune
response.  IL-4 and IL-13 signaling occurs through Type I and II IL-4 receptors
(IL-4 through both receptors and IL-13 through Type II receptors), which both
contain a common IL-4R alpha subunit. 
About Dupilumab (SAR231893/REGN668)
Dupilumab is a fully human monoclonal antibody directed against IL-4R alpha and
is administered via subcutaneous injection.  By blocking IL-4R alpha dupilumab
modulates signaling of both IL-4 and IL-13, drivers of a Th2 immune response.
Dupilumab was created using Regeneron's pioneering VelocImmune(r) technology and
is being co-developed with Sanofi. Dupilumab is currently being studied in both
atopic dermatitis and asthma. 
About Asthma
Asthma is a chronic inflammatory disease of the airways characterized by airway
sensitivity to environmental and biologic factors such as dust, chemicals,
smoke, allergens, and viral infections leading to an acute and chronic narrowing
of the airway and increased mucus production. Patients with asthma can
experience wheezing, shortness of breath, cough and chest tightness, and in
severe cases, these symptoms can be life-threatening. For most asthma patients, 
currently available treatments can control the disease.  However, an estimated
10% to 20% of asthmatic patients are less than optimally controlled despite
existing therapies.  Moderate-to-severe asthma can negatively impact the lives
of patients and is associated with a high burden to society both in terms of
direct costs of medical care and prescription drugs, as well as loss of
productivity. Moderate-to-severe asthma is recognized as a heterogeneous
disease; the Th2 inflammation pathway is believed to play a role in disease
pathogenesis in approximately 50% of these patients. It is estimated that
approximately 25 million people in the United States are known to have asthma.
The worldwide estimates are between 235-300 million people, with 180,000 deaths
annually. 
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 Regeneron Pharmaceuticals, Inc.
Regeneron is a leading science-based biopharmaceutical company based in
Tarrytown, New York that discovers, invents, develops, manufactures, and
commercializes medicines for the treatment of serious medical conditions.
Regeneron markets medicines for eye diseases, colorectal cancer, and a rare
inflammatory condition and has product candidates in development in other areas
of high unmet medical need, including hypercholesterolemia, oncology, 
rheumatoid arthritis, allergic asthma, and atopic dermatitis. For additional 
information about the company, please visit www.regeneron.com. 
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ended December 31, 2012. Other than as required by applicable law, Sanofi does
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Regeneron Forward-Looking Statements
This news release includes forward-looking statements that involve risks and
uncertainties relating to future events and the future performance of Regeneron,
and actual events or results may differ materially from these forward-looking
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include, among others, the nature, timing, and possible success and therapeutic
applications of Regeneron's products, product candidates, and research and
clinical programs now underway or planned; including without limitation
dupilumab; unforeseen safety issues resulting from the administration of
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be cancelled or terminated without any further product success; and risks
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December 31, 2012 and our From 10-Q for the quarter ended March 31, 2013.
Regeneron does not undertake any obligation to update publicly any
forward-looking statement, including  without limitation any financial
projection or guidance, whether as a result of new information, future events,
or otherwise, unless required by law. 
Contacts: 
Sanofi:
Media Relations                       Investor Relations
Marisol Péron                         Sébastien Martel
Tel: +33 (0) 1 53 77 45 02            Tel: +33 (0)1 53 77 45 45
Mobile: +33 (0) 6 08 18 94 78         E-mail: IR@sanofi.com
E-mail: marisol.peron@sanofi.com 
Regeneron:
Media Relations                       Investor Relations
Peter Dworkin                         Manisha Narasimhan, Ph.D.
Tel: 1 (914) 847-7640                 Tel: 1 (914) 847-5126
peter.dworkin@regeneron.com           manisha.narasimhan@regeneron.com 
                  
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-0- May/21/2013 12:40 GMT