UPDATE 2-New Glaxo orders point to big flu vaccine windfall

* 149 mln doses ordered since August, total now 440 mln

* Implies booked orders to date worth around $3.5 bln

* Discussions continue with governments for further supplies

* First shipments of H1N1 vaccine this week

(Adds analyst comment, shares, background)

By Ben Hirschler

LONDON, Oct 6 (Reuters) - GlaxoSmithKline Plc (GSK.L) won a further 22 government orders for its H1N1 swine flu vaccine in the last two months, taking the total number of doses ordered to 440 million worth some $3.5 billion.

The Britain-based drugmaker said on Tuesday first supplies were being shipped to governments this week and deliveries would continue through both the fourth quarter of 2009 and the first half of 2010.

The addition of a further 149 million orders since Aug. 4, when Glaxo last gave an update, points to a substantial sales and profit windfall as a result of the swine flu pandemic.