The drug has been offered to those with close contact to swine flu
Swiss drugs firm Roche has seen sales of Tamiflu - the main drug being used to fight the swine flu pandemic - rise by 200% in the first half of the year.
Sales of the drug hit 1bn Swiss francs ($937m; £567m), as Roche said Tamiflu production would be expanded to 400 million packs annually by early 2010.
But Roche saw first-half net profits fall by 29% to 4.1bn Swiss francs.
That was mainly due to costs related to the takeover of its California-based partner Genentech.
In March Roche paid $46.8bn to buy the remaining 45% of Genentech that it did not already own.
"I am especially pleased about the excellent progress we've made in integrating Roche and Genentech," said chief executive Severin Schwan.
"Work at Genentech's research and early development centre in South San Francisco has continued seamlessly with the existing management team."
Mr Schwan said the company would be benefiting from the synergies of the merger sooner than originally envisaged.
He also said Roche had one of the the "strongest development portfolios in the industry".