LONDON - British drug delivery expert SkyePharma said on Tuesday it was likely U.S. authorities would need more data on its flagship product, Flutiform, thereby delaying its approval.

The company has received a 74-day letter from U.S. officials over asthma treatment Flutiform, and said that, based on a preliminary assessment, it seems likely that further clinical work would be required, delaying the approval process.

Potentially it is significant because there might be more data needed, but it's not significant enough for me to start reviewing my financial model at this point, said analyst Jacob Plieth at Edison Investment Research, adding that it was an unknown issue until the company meets with the FDA.

The company's shares had fallen around 7 percent by 1436 GMT.

SkyePharma is partnering with Abbott Laboratories (ABT.N) in the United States and with Mundipharma in Europe, where Flutiform is expected to be filed for approval in the first quarter of 2010.

Last September, the company completed the renegotiation of terms of its convertible bonds and raised funds, giving it cash and undrawn facilities of 37.5 million as of Dec. 31, 2008, which it said was sufficient to meet the needs of the business for the foreseeable future.

(Reporting by Ben Deighton; editing by Simon Jessop)