Europe approves Sanofi's intradermal flu vaccine

Editor's note: This story was updated Feb 27 to include more information about an intradermal vaccine that Sanofi Pasteur is developing for the US market.

Feb 26, 2009 (CIDRAP News) – The European Union has approved the first influenza vaccine injected with a shallow needle prick into the skin instead of a jab all the way into muscle, according to Sanofi Pasteur, the vaccine's manufacturer.

In a news release, the company said the intradermal (ID) vaccine, to be marketed as Intanza or IDflu, should improve flu immunization rates in Europe because of its convenience and ease of administration.

"This is the first major market license for Intanza/IDflu and a key step towards recognition of the ID route as a promising alternative for influenza vaccine administration," Sanofi President Wayne Pisano said in the news release.

The vaccine was approved for use in adults, including those over 60, the company said. The approval by the European Commission follows endorsement of the vaccine in December by the European Medicines Agency's Committee for Medicinal Products for Human Use.

The company said ID vaccination—injecting a vaccine into the dermal layer of the skin—offers a special advantage: "Due to the high concentration of specialized immune cells in this skin layer and their ability to effectively stimulate an immune response, ID vaccination provides direct and efficient access to the immune system."

Sanofi tested Intanza in clinical trials involving more than 7,000 adult and elderly volunteers, the company reported in December. In a phase 3 trial involving more than 3,000 volunteers over age 60, Intanza was well tolerated and induced a stronger immune response when given intradermally than intramuscularly, officials said.

The vaccine is delivered with an injection system that was developed in collaboration with Becton Dickinson, consisting of a prefilled syringe with a shielded needle that can penetrate only 1.5 millimeters into the skin, according to a 2007 report in Vaccine. ID vaccinations previously were done with the Mantoux technique, developed for tuberculosis skin tests, but that method is not very reliable or efficient, the report said.

Sanofi said the injection system "allows for minimally invasive vaccination and ensures that the antigen is accurately and consistently deposited in the dermal layer of the skin."

In clinical trials, the vaccine met good acceptance from recipients, and vaccinators liked its convenience, said Pisano. "The comfort benefits offered by Intanza/IDflu have the potential to improve the coverage rate and consequently to help to protect more people and save more lives," he added.

Sanofi is also developing an ID version of its US-licensed seasonal flu vaccine, Fluzone. "We are currently in phase 3 trials, and we expect to submit an application to the FDA [Food and Drug Administration] in 2010," Len Lavenda, a company spokesman in Swiftwater, Pa., told CIDRAP News. He said the vaccine uses the same injection system as the European version.

The US flu vaccine shortage in the 2004-05 flu season generated interest in using ID vaccination as a way to stretch the vaccine supply, according to the Vaccine report. But Sanofi officials have said that standard doses were used in the clinical trials of Intanza.

See also:

Feb 26 Sanofi news release

Dec 22, 2008, CIDRAP News story on preliminary EU approval of Intanza

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