* Half a dose may be enough for immune response
* Use of adjuvant could quadruple vaccine supply
ZURICH Nov 17 A U.S. clinical study suggests
that just half a dose of the Novartis AG NOVN.VX H1N1 vaccine
may be enough to generate a protective immune response, the
Swiss drugmaker said on Tuesday.
Novartis said data from about 4,000 individuals suggested
that half a dose of its U.S.-approved unadjuvanted H1N1 vaccine
met immune criteria in adults and the elderly.
The data also showed that its adjuvant was well tolerated,
which could potentially quadruple the Novartis vaccine supply.
Adjuvanted vaccines contain an additive to boost the immune
system response and need less of the active ingredient than the
unadjuvanted types approved by the U.S. Food and Drug
U.S. health officials have been scrambling to get the swine
flu vaccine to market after the virus emerged too late to be
included in this year's regular seasonal flu version.
Initially, officials said there would be enough for
everyone, but the public quickly grew frustrated when supplies
The FDA has approved H1N1 vaccine from five makers who
already produce seasonal flu vaccine -- GlaxoSmithKline Plc
(GSK.L), AstraZeneca Plc's (AZN.L) MedImmune unit, Novartis
NOVN.VX, Sanofi-Aventis (SASY.PA), and CSL Limited (CSL.AX).
(Reporting by Emma Thomasson; Editing by Catherine Bosley and