Blackstone Group LP's banking unit had an advantage in competing for the mandate to advise Stiefel Laboratories Inc. on its sale to GlaxoSmithKline plc: In 2007, Blackstone made a $500 million investment in privately held Stiefel, a pharmaceuticals group specializing in dermatology. Blackstone's Jeffrey Pribyl and Mary Anne Citrino advised Coral Gables, Fla.-based Stiefel on the sale, announced April 20. GlaxoSmithKline will pay $2.9 billion in cash and assume $400 million in debt. The buyer may pay Stiefel shareholders as much as $300 million more if it meets certain performance targets.

On the legal side, Stiefel tapped ­William Grant Jr. and Gregory Astrachan of Willkie Farr & Gallagher LLP. The law firm first worked for Stiefel on its $640 million acquisition of Connetics Corp. Willkie was one of three firms that Deutsche Bank AG, Stiefel's financial adviser on the Connetics deal, recommended to the company. Grant and Willkie's Thomas Mark advised Stiefel on the Blackstone investment.

For legal advice, GlaxoSmithKline turned to Benet O'Reilly at Cleary Gottlieb Steen & Hamilton LLP, which has handled several acquisitions for the drugmaker in recent years, including the $720 million purchase of Sirtris Pharmaceuticals Inc. last year; the $1.65 billion acquisition of Reliant Pharmaceuticals Inc. in 2007; the purchases of CNS Inc. for $566 million and Praecis Pharmaceuticals Inc. for $55 million in 2006; and, in 2005, the acquisitions of ID Biomedical Corp. for $1.4 billion and Corixa Corp. for $300 million. Glaxo Wellcome plc often used Simpson Thacher & Bartlett LLP before its 2000 tie-up with SmithKline Beecham plc.

On the banking side of the Stiefel Labs deal, Glaxo engaged the services of Lazard's Kenneth Jacobs, Alexis de Rosnay and David Gluckman.