Unadjuvanted vaccine approved -- for some

TORONTO -- Clinics and doctors across the country were given the green light Friday to start using 1.8 million doses of H1N1 vaccine made without adjuvant -- but they were told not to give it to one of the originally intended recipient groups.

Health Canada approved the GlaxoSmithKline-made vaccine for pregnant women and healthy individuals aged 10 to 64. But the vaccine isn't to be used in people 65 and older, people with impaired immune systems and children under 10, the regulator said.

"Under the age of 10 adjuvanted (vaccine) is clearly preferred and produces much better immunity," said Dr. David Butler-Jones, Canada's chief public health officer.

The GSK vaccine -- the lion's share of two million doses of unadjuvanted vaccine bought by Canada -- was originally intended for pregnant women and children under age three. The rationale for the special purchase was that there were little if any data on the use of adjuvanted flu vaccine in these groups.

The remainder of the unadjuvanted vaccine was bought from Australian vaccine maker CSL. It was approved earlier and has been offered as of this week.

An estimated 300,000 to 350,000 Canadian women are pregnant in any given year. The rest of the vaccine was destined for young children.

But authorities at the Public Health Agency of Canada have become convinced any theoretical safety concerns about adjuvants -- which boost the immune response to the vaccine -- are evaporating as tens of millions of people worldwide have been vaccinated with the adjuvanted H1N1 vaccine.

And with studies suggesting the adjuvanted product induces a stronger immune response in children, the decision was made not to use it in that age group.

"It's pretty clear that the adjuvanted vaccine for children under the age of 10 is clearly superior and is a very good and safe vaccine," Butler-Jones said.

-- The Canadian Press

Republished from the Winnipeg Free Press print edition November 14, 2009 A9