Chiron revealed late on Friday that the US Securities and Exchange Commission had launched a formal investigation into whether the company had broken federal securities laws.

The SEC’s inquiry initially took the form of an informal investigation, which was prompted by the UK regulators’ decision to halt shipments of the company’s flu vaccine, Fluvirin, after manufacturing deficiencies were uncovered at Chiron’s Liverpool, UK, plant [[06/10/04b]]. The move triggered a health catastrophe in the USA, leaving the country with just half its planned 100 million flu vaccine doses for the season. Chiron has also been hit by a US grand jury subpoena [[13/10/04a]], and a US Food and Drug Administration warning letter in connection with the manufacturing facility at the centre of the furore [[13/12/04b]]. The company has also seen its financials suffer as a result of not being able to record any Fluvirin sales in either the third or fourth quarters of the year, and had to write off the entire Fluvirin vaccine product inventory in the third quarter [[28/01/05e]].

Chiron said it was continuing to cooperate with the SEC’s ongoing investigation.