Drugmaker Abbott Laboratories has decided against the sale of its European flu-vaccine business after initial bids came in below its expectations, a company spokeswoman confirmed.

The auction had drawn interest from four or five bidders, but the offers came in at less than €500 million euros ($640 million) and proved too low for the company's liking, a person familiar with the matter told the newspaper.

"We explored the option of potentially selling the vaccine business...We have (now) decided to retain it," Abbott spokeswoman Melissa Brotz confirmed by phone. She said the company will now integrate the unit into its other businesses.