The Lancet Infectious Diseases Publishes New Health Economic Analysis Comparing Use of Higher-Dose Influenza Vaccine to Standard-Dose Vaccine in Seniors

Swiftwater, Pa., – September 9, 2015 – Sanofi Pasteur, the vaccines division of Sanofi, announced today that The Lancet Infectious Diseases published positive results from a new economic analysis. The analysis uses data from a large-scale, multi-center efficacy trial, in which a higher-dose split-virus inactivated influenza vaccine (IIV-HD) was compared to a standard-dose split-virus inactivated influenza vaccine (IIV-SD) in persons 65 years of age and older. These data were supplemented with US healthcare cost data.

In the efficacy trial, a total of 31,989 adults 65 years of age and older were randomly assigned in a 1:1 ratio to receive either IIV-HD (Fluzone® High-Dose vaccine, Sanofi Pasteur) or IIV-SD (Fluzone vaccine, Sanofi Pasteur) and followed for six to eight months post-vaccination for the occurrence of influenza, serious adverse events and medical encounters. Healthcare utilization (HCU) data were captured for all participants through a surveillance program that covered each influenza season, including the following events occurring within 30 days after any respiratory illness: use of prescription and non-prescription medications (limited to antipyretics/analgesics/non-steroidal anti-inflammatory drugs, antivirals and antibiotics), emergency room visits, non-routine or urgent care visits, and hospitalizations. In addition, all hospitalizations were captured for participants for the entire duration of the study.

The primary results from the efficacy trial were published in The New England Journal of Medicine, which reported that IIV-HD was 24.2% (95% confidence interval [CI], 9.7% to 36.5%) more effective in preventing laboratory-confirmed influenza-like illness compared to IIV-SD.[i] In the current supplemental analysis of the trial, Dr. Ayman Chit, PhD, Senior Director, Health Economics, Modeling and Market Access, North America, Sanofi Pasteur US, and his colleagues used US healthcare cost data to evaluate economic impacts of using IIV-HD compared to IIV-SD within the efficacy trial participants.

About Fluzone High-Dose (Influenza Vaccine) Indication
Fluzone High-Dose vaccine is indicated for active immunization for the prevention of influenza disease caused by influenza A subtype viruses and type B virus contained in the vaccine.

Fluzone High-Dose vaccine is approved for use in persons 65 years of age and older.

Safety Information
The most common local and systemic adverse reactions to Fluzone High-Dose vaccine include pain, erythema, and swelling at the injection site; myalgia, malaise, headache, and fever. Other adverse reactions may occur. Fluzone High-Dose vaccine should not be administered to anyone with a known hypersensitivity (eg, anaphylaxis) to any vaccine component, including egg protein, or to a previous dose of any influenza vaccine.

If Guillain-Barré syndrome has occurred within 6 weeks following previous influenza vaccination, the decision to give Fluzone High-Dose vaccine should be based on careful consideration of the potential benefits and risks. Vaccination with Fluzone High-Dose vaccine may not protect all individuals.

Before administering Fluzone High-Dose vaccine, please see accompanying full Prescribing Information.

About The Lancet Infectious Diseases
The Lancet Infectious Diseases was launched in August, 2001, and is a lively monthly journal of original research, review, opinion, and news covering international issues relevant to clinical infectious diseases specialists worldwide.

About Sanofi
Sanofi, a global healthcare leader, discovers, develops and distributes therapeutic solutions focused on patients' needs. Sanofi has core strengths in diabetes solutions, human vaccines, innovative drugs, consumer healthcare, emerging markets, animal health and Genzyme. Sanofi is listed in Paris ((EURONEXT: SAN) and in New York (NYSE: SNY).

Sanofi Pasteur, the vaccines division of Sanofi, provides more than 1 billion doses of vaccine each year, making it possible to immunize more than 500 million people across the globe. A world leader in the vaccine industry, Sanofi Pasteur offers a broad range of vaccines protecting against 20 infectious diseases. The company's heritage, to create vaccines that protect life, dates back more than a century. Sanofi Pasteur is the largest company entirely dedicated to vaccines. Every day, the company invests more than EUR 1 million in research and development. For more information, please visit: or

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[i] DiazGranados CA, Dunning AJ, Kimmel M, et al. Efficacy of high-dose versus standard-dose influenza vaccine in older adults. N Engl J Med 2014; 371:635-645.