Second test backs single dose of Glaxo H1N1 shot

LONDON (Reuters) - GlaxoSmithKline said on Friday a second clinical trial of its adjuvanted H1N1 swine flu vaccine Pandemrix had confirmed that a single dose could provide a strong immune response.

Glaxo's vaccine -- containing an additive, or adjuvant, to boost its effectiveness -- was approved for use in Europe last month. It has not been cleared for use in the United States.

Experts had initially expected adults would need two doses of H1N1 vaccine to get a good response. But clinical trials with shots from companies including Glaxo, Sanofi-Aventis, Novartis and CSL now suggest one dose is probably enough.

The British-based drugmaker recently started sending supplies of Pandemrix to governments and said it had delivered more than 7 million doses in the first week of shipments, adding that deliveries would increase in the coming weeks.

Britain is one of the first countries to receive the vaccine. Officials said on Thursday that millions of doses of the Glaxo vaccine would be available for use throughout the state health service by the end of this month. [ID:nLF319273]

(Reporting by Ben Hirschler)