Beyfortus real-world evidence published in The Lancet shows 82% reduction in
infant RSV hospitalizations

  * New real-world evidence shows Beyfortus (nirsevimab) substantially reduced
    RSV lower respiratory tract disease and hospitalizations in infants during
    the 2023-2024 RSV season, versus no intervention(1)(-6)
  * Results add to the consistent high efficacy of Beyfortus against medically
    attended RSV lower respiratory tract disease, shown in the pivotal clinical
    studies and the outcomes from HARMONIE, a phase 3b clinical study conducted
    in close to real-life conditions(7-1)(0)

Paris, May 2, 2024. Beyfortus reduced respiratory syncytial virus (RSV)
hospitalizations by 82% (95% CI: 65.6 to 90.2) in infants under 6 months of age,
compared to infants who received no RSV intervention, according to the interim
results of an ongoing study published in The Lancet
(https://www.thelancet.com/journals/laninf/article/PIIS1473-
3099(24)00215-9/abstract). These results, from the first RSV season after
Beyfortus' introduction, are part of the three-year NIRSE-GAL study conducted in
Galicia, Spain under a collaborative framework with the Galician Directorate of
Public Health of the Xunta de Galicia (Galician government) and Sanofi.(1)
The results echo real-world evidence (RWE) reported from several broad infant
immunization programs across the US, Spain and France during the 2023-2024 RSV
season, which add to the consistent and high efficacy seen in pivotal clinical
studies with Beyfortus. Real-world evidence demonstrates if a treatment or
immunization is effective in day-to-day practice, as opposed to "efficacy"
determined in carefully controlled clinical trials. A favorable safety profile
was observed following Beyfortus use, consistent with clinical study
results.(1)(-10)
Federico Martinon Torres
Head of Pediatrics, Hospital Clínico Universitario Santiago, Spain and principal
investigator of NIRSE-GAL study
"Galicia provides the first population-based real-world evidence of the impact
of nirsevimab to prevent RSV disease in infants, showing a reduction by almost
90% in the number of hospitalizations due to this virus when compared with
several previous RSV seasons. This achievement is the result of the exemplary
pragmatic collaboration among scientists, industry, healthcare providers and
policy makers aligned with a carefully planned roll-out of the immunization
campaign, and the outstanding response of the Galician parents to this
prophylaxis campaign."
Thomas Triomphe
Executive Vice President, Vaccines, Sanofi
"The scale and speed of impact seen after Beyfortus' introduction demonstrates
the strength of all-infant immunization strategies against RSV in babies. In
Galicia, we saw an effectiveness of 82% in reducing RSV hospitalizations
following the launch of Beyfortus, with more than 90% of eligible infants
immunized. A growing body of evidence from these programs support policymakers,
healthcare providers and parents who share our collective ambition to safeguard
babies from RSV disease."
NIRSE-GAL (http://www.nirsegal.es/) is a large, population-based, three-year
follow-up study to evaluate the effectiveness of Beyfortus following its
inclusion in the Galician immunization schedule. The study aims to measure the
impact of Beyfortus on hospitalizations due to RSV, all-cause lower respiratory
tract disease, severe lower respiratory tract disease caused by RSV, all-cause
lower respiratory tract disease hospitalizations, and all-cause hospitalizations
among infants born during the RSV season, infants under 6 months of age at the
start of the season, and children aged 6-24 months who are vulnerable to severe
RSV disease at the start of the season. The 2023-2024 immunization campaign ran
from September 25, 2023 to March 31, 2024.(1)
RWE from countries with Beyfortus all-infant immunization programs in 2023-24
In addition to this new effectiveness study, evidence of the high impact
following Beyfortus' introduction has been consistently shown in several other
real-world studies.
* An interim analysis of 2023-24 surveillance data published in the US Centers

    for Disease Control and Prevention's (CDC) Morbidity and Mortality Weekly
    Report (https://www.cdc.gov/mmwr/volumes/73/wr/mm7309a4.htm) (MMWR) shows a
    single dose of Beyfortus was 90% effective in preventing hospitalizations
    due to RSV in babies who were immunized below 8 months of age.(2)

* A recent draft recommendation from Haute Autorité de Santé (https://www.has- sante.fr/upload/docs/application/pdf/2024-
03/recommandation_vaccinale_contre_les_infections_a_vrs_chez_les_femmes_ence intes_-_version_provisoire.pdf) in France reported, across six hospitals, an

    effectiveness of 83% against RSV-associated hospitalization in infants who
    received Beyfortus compared to those with no intervention.(3)
  * In Catalonia, Spain, a study pre-printed in The Lancet
    (https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4749763) showed
    reductions of 87.6% and 90.1% in hospital and ICU admissions for RSV,

respectively, among babies born before the start of the RSV season, who were

    eligible to receive Beyfortus, compared to those with no intervention.(4)
  * A pooled analysis of data from three Spanish regions, including Valencia,
    Murcia, and Valladolid, showed an 84.4% effectiveness in preventing
    hospitalizations due to RSV in infants under 9 months of age versus infants

who received no intervention. The results were published in Eurosurveillance

    (https://www.eurosurveillance.org/content/10.2807/1560-
    7917.ES.2024.29.6.2400046).(5)
  * A study from Navarra, Spain published in Vaccines

(https://www.mdpi.com/2076-393X/12/4/383) found an effectiveness of 88.7% in preventing hospitalizations among infants immunized at birth with Beyfortus, compared to no intervention.(6)
The expansion of the Beyfortus manufacturing network is progressing well and
according to plan. This expansion will allow Sanofi and AstraZeneca to more than
triple manufacturing capacity. Based on this, and assuming regulatory
validations are delivered in due time by regulatory agencies, Sanofi and
AstraZeneca are confident to meet global commitments and build inventory that
can be used in future RSV seasons. In addition, the companies are producing
Beyfortus well in advance of the RSV season, with the vast majority of doses
planned to be available by October.
About RSV
RSV is a highly contagious virus that can lead to serious respiratory illness
for infants.(1)(1) Two out of three infants are infected with RSV during their
first year of life and almost all children are infected by their second
birthday.(1)(1)(,1)(2) RSV is the most common cause of lower respiratory tract
disease, including bronchiolitis and pneumonia, in infants.(1)(3) It is also a
leading cause of hospitalization in infants worldwide, with most
hospitalizations for RSV occurring in healthy infants born at term.(1)(4)(-
1)(7) Globally, in 2019, there were approximately 33 million cases of acute
lower respiratory infections leading to more than 3 million hospitalizations,
and it was estimated that there were 26,300 in-hospital deaths of children
younger than 5 years.(1)(8) RSV-related direct medical costs, globally -
including hospital, outpatient and follow-up care - were estimated at EUR4.82
billion in 2017.(19)
About Beyfortus
Beyfortus (nirsevimab) is the first immunization designed for all infants for
protection against RSV through their first RSV season, including for those born
healthy at term or preterm, or with specific health conditions that make them
vulnerable to RSV disease. Beyfortus is also designed to protect children up to
24 months of age who remain vulnerable to severe RSV disease through their
second RSV season.
As a long-acting antibody provided directly to newborns and infants as a single
dose, Beyfortus offers rapid protection to help prevent lower respiratory tract
disease caused by RSV without requiring activation of the immune system.
Beyfortus administration can be timed to coincide with the RSV season.
In March (https://www.sanofi.com/en/media-room/press-releases/2017/2017-
03-03-07-00-00-931162) 2017 (https://www.sanofi.com/en/media-room/press-
releases/2017/2017-03-03-07-00-00-931162), Sanofi and AstraZeneca announced an
agreement to develop and commercialize Beyfortus. Under the terms of the
agreement, AstraZeneca leads development and manufacturing activities and Sanofi
leads commercialization activities and records revenues. Under the terms of the
global agreement, Sanofi made an upfront payment of EUR120m, has paid development
and regulatory milestones of EUR120m and will pay up to a further EUR375m upon
achievement of certain regulatory and sales-related milestones. The two
companies share costs and profits in all territories except in the US where
Sanofi consolidates 100% of the economic benefits in its Business Operating
Income.
Beyfortus has been approved for use in the European Union, the US, China, Japan,
and many other countries around the world. Special designations to facilitate
expedited development of Beyfortus were granted by several regulatory agencies,
including Breakthrough Therapy Designation and Priority Review designation by
The China Center for Drug Evaluation under the National Medical Products
Administration; Breakthrough Therapy Designation and Fast Track Designation from
the US Food and Drug Administration; access granted to the European Medicines
Agency (EMA) PRIority MEdicines (PRIME) scheme and EMA accelerated assessment;
Promising Innovative Medicine designation by the UK Medicines and Healthcare
products Regulatory Agency; and Beyfortus has been named "a medicine for
prioritized development" under the Project for Drug Selection to Promote New
Drug Development in Pediatrics by the Japan Agency for Medical Research and
Development.
About Sanofi
We are an innovative global healthcare company, driven by one purpose: we chase
the miracles of science to improve people's lives. Our team, across the world,
is dedicated to transforming the practice of medicine by working to turn the
impossible into the possible. We provide potentially life-changing treatment
options and life-saving vaccine protection to millions of people globally, while
putting sustainability and social responsibility at the center of our ambitions.
Sanofi is listed on EURONEXT: SAN and NASDAQ: SNY
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