The US expects to begin distributing vaccines against the 2009 H1N1 influenza virus within the next four weeks after the Food and Drug Administration (FDA) announced approval for four vaccines.
The approval for the vaccines, produced by CSL Limited, MedImmune LLC, Novartis Vaccines and Diagnostics Limited and Sanofi Pasteur, was based on preliminary data from multiple clinical studies, all of which showed robust immune responses in adults after a single dose.
US Health Secretary Kathleen Sebelius said that the 195 million doses of swine flu vaccine purchased by the government would be made available free of charge starting next month. Vaccine outlets, however, may charge a fee to administer the doses.
Food and Drugs Commissioner Margaret A Hamburg said that the approval was good news.
"This vaccine will help protect individuals from serious illness and death from influenza," Hamburg said.
The approved vaccines have been shown to elicit a good response in adults; the recommended dosing for children, however, is expected to be updated based on the results of clinical trials now underway.
The FDA has warned that potential side effects are expected to be similar to seasonal flu vaccines and could include soreness at the injection site, mild fever, body aches and fatigue.
People with severe or life-threatening allergies to chicken eggs, or to any other substance used in the vaccine, have been warned not to be vaccinated.
Three of the approved vaccines come in the form of an injectable monovalent vaccine and the fourth vaccine, produced by MedImmune LLC, will be available as a nasal spray.
By Daniel Garrun.