* Prices 20 pct more shares than planned at top end of range
* Stock rally encouraging PE firms to exit investments
* This week could be heaviest IPO week since late 2007
By Olivia Oran
May 8 (Reuters) - Drug researcher Quintiles TransnationalHoldings raised a more-than planned $947 million in itsIPO, the latest listing from a private equity-backed company asrecord highs for U.S. stocks encourage more exits frominvestments.
Strong investor demand for the deal helped Quintiles, whichis backed by Bain Capital LLC and TPG Capital LP, price 20percent more shares than expected at the top end of the rangeand pushed up pricing a day early, according to people familiarwith the deal.
Other public floats from private equity-backed companiesthis year have included Norwegian Cruise Line Holdings Ltd, SeaWorld Entertainment Inc, Pinnacle FoodsInc and Intelsat SA.
The Durham, North Carolina-based conductor of clinicaltrials is also the largest of eleven IPOs pricing this week,which could mark the highest weekly IPO volume since late 2007,according to market data firm Ipreo.
It priced 23.7 million shares at $40, compared with its plan to price 19.7 million shares at $36 to $40.
Other deals which have priced this week include residentialmortgage company PennyMac Financial Services Inc andbiotech company Receptos Inc.
Bain and TPG became the lead investors in Quintiles inJanuary 2008 after One Equity Partners sold its stake in thecompany. Britain's 3i Group Plc and Singapore's TemasekHoldings are also investors in Quintiles.
Quintiles sold 13.1 million shares in the IPO. The company'sfounder and executive chairman Dennis Gillings and the privateequity firms sold the remaining 10.6 million shares.
It will use IPO proceeds to pay outstanding debt, toterminate a management agreement with its private equitysponsors and for general corporate purposes.
Quintiles generated adjusted earnings before interest, tax,depreciation and amortization of $177.5 million on revenue of$4.9 billion in the year ended Dec. 31, 2012.
The company's rivals include Covance Inc, ICON andParexel International, according to Morningstar.
Morgan Stanley, Barclays and JPMorgan are the leadunderwriters on the offering.
Quintiles will list its shares on the New York StockExchange under the symbol Q.