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By Freya Berry
LONDON, March 13 (Reuters) - British allergy drug development firm Circassia priced its initial public share offer at the top of its range on Thursday, in the biggest London market debut in years for a biotech company.
The listing at 310 pence per share values the company at about 581 million pounds ($965 million), making it the largest biotech IPO since at least 1995, according to life science publication EP Vantage.
The price was flat at 310 pence in conditional trading at 0943 GMT, the London Stock Exchange said, off a session high of 316.75 pence.
The last major IPO in the sector was Ark Therapeutics AKT.L which raised 55 million pounds ($91.3 million) in London in 2004.
Circassia is raising 200 million pounds ($332 million) before costs in its share sale to help bring to market a vaccine for cat allergies. In addition existing shareholders are selling shares worth 9 million pounds, the company said.
The price range for the company, which is 20 percent owned by British universities-backed company Imperial Innovations , had been set at 250 pence to 310 pence. JP Morgan Cazenove and Peel Hunt were joint book runners on the offer.
Biotech saw a renaissance in the United States last year with dozens of listings, but it remains to be seen whether the trend can be replicated in Europe.
Many firms opt for the tech-focused Nasdaq exchange rather than a European listing, in order to access capital from investors experienced in the biotech industry. Britain's Lombard Medical this week decided to delist from London and switch to Nasdaq with an $80 million IPO there.
"The US market has taken off over the last 12 months," said Chief Executive Steven Harris, adding that Europe looked set to follow suit.
"There was a warm reception in London," he said.
The sector has proven to be highly volatile in the past, as seen with the sudden rise and fall of experimental cancer drug firm British Biotech in the 1990s, while Ark Therapeutics has lost 99.6 percent of its share value since its debut. ($1=0.6022 pounds) (Reporting By Freya Berry; Editing by Greg Mahlich)