(AP) -- Drug giant GlaxoSmithKline says one of its swine flu vaccines has been certified by the World Health Organization, making it available for donors to buy for developing countries.

In a statement issued Tuesday, GlaxoSmithKline PLC said WHO had approved its Canadian vaccine after examining its quality and safety data. The vaccine contains an adjuvant, a to boost the immune system.

Last month, Glaxo advised health authorities not to use one batch of its Canadian-manufactured vaccine in case it triggered life-threatening side effects like anaphylactic shock.

Several vaccine makers have promised WHO 156 million doses of swine flu , which it hopes to start shipping to 95 poor countries this month.

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