GlaxoSmithKline said on Monday a single shot of it''s A(H1N1) swine flu vaccine protected people from the virus , adding to evidence that tight supplies can be stretched further by avoiding the need for two doses. The British drug maker is the latest pharmaceutical company to report success with a single dose. Results from the first clinical trial with its candidate vaccine showed nearly 100 percent protection three weeks after vaccination.
A single dose of Glaxo''s adjuvanted vaccine protected 98 percent of healthy volunteers, even though it contained a lower than normal amount of antigen, or active ingredient. Adjuvants are immuneـstimulating compounds added to vaccines to boost their effectiveness.
In fact, Glaxo''s adjuvanted vaccine, containing 5.25 micrograms of antigen, performed far better after three weeks than the unadjuvanted one, with 21 micrograms, in the 130ـpatient trial conducted in Germany. A(H1N1) swine flu vaccines would be given separately from regular seasonal flu shots and pandemic sales to governments are expected to provide a sales windfall for many manufacturers this year and next.
"This trial provides encouraging data on the potential use of a single dose of our pandemic vaccine," said Glaxo vaccines Head Jean Stephenne. The final formulation of Glaxo''s adjuvanted vaccine is expected to have just 3.75 micrograms of antigen.
Because it is a new strain, infectious diseases'' experts had initially anticipated people would likely need two doses of any A(H1N1) vaccine, given three weeks apart, to get full immunity against swine flu.ـ

Alwatan Daily