Biovail Corp. and Valeant Pharmaceuticals International both hired new CEOs two years ago. One of those executives brought in a new team of lawyers who worked on the biotechnology companies' merger of equals, announced June 21, while the other retained long-standing counsel.

William Wells took the reins at Mississauga, Canada-based Biovail in 2008 after founder Eugene Melnyk ran into legal trouble in both the U.S. and Canada and stepped down from the company's board in 2007. Cravath, Swaine & Moore LLP's Erik Tavzel began advising Biovail with the change in management and counseled it on the Valeant deal, along with Cravath partners George "Jed" Zobitz, Eric Hilfers on executive compensation and benefits, and Michael Schler on tax. David Toswell of Canadian law firm Blake, Cassels & Graydon LLP began working for Biovail around the same time and was co-counsel with Cravath on the Valeant deal.

For banking advice, Biovail tapped Joseph Modisett, Tedd Smith and Michael Boublik of Morgan Stanley with Whit Marshall and Christy Silvester on the leveraged finance side. The bank worked with Wells when he became CEO and advised the company when Melnyk launched a proxy fight in 2008. Biovail won the battle, and Melnyk sold his remaining 6.2% stake in the company earlier this year.

Biovail's special committee used Alison Ressler of Sullivan & Cromwell LLP in Los Angeles. Laurence Paul, a Biovail board member and founding partner of Los Angeles buyout shop Laurel Crown Partners LLC, originally recommended Ressler when the Biovail board formed a special committee to respond to Melnyk's proxy fight.

Michael Pearson didn't opt for such changes when he was named CEO at Valeant two years ago. Valeant used Stephen Arcano and Jeffrey Brill of Skadden, Arps, Slate, Meagher & Flom LLP and Gino Martel of Ogilvy Renault LLP on the Biovail deal. Ogilvy has worked for Valeant for 10 years. Arcano first worked for Valeant in 2003, when it acquired the 20% of subsidiary Ribapharm Inc. that it didn't already own. He also advised Valeant on the 2008 sale of its Western European business for $392 million to Medea AB.

Robert King, Tosa Ogbomo, Dusty Philip and Doretta Mistras of Goldman, Sachs & Co. provided banking advice on the deal with Robert Steininger and Matt Miller of Jefferies & Co. Mike Leder of Jefferies and Christina Minnis, Jean Joseph and Jeff Warren of Goldman advised on the acquisition financing side.

Steininger worked on a financing deal for Valeant in June 2009 when he was at UBS. He moved to Jefferies in August with Benjamin Lorello and worked on another Valeant financing this May.

Goldman advised Valeant on the Medea deal and its 2008 purchase of Dow Pharmaceutical Sciences Inc. for $285 million, as well as on financings in 2009 and this year.

Pearson, who came to Valeant after 23 years at ­McKinsey & Co., is using Lawrence Cagney of Debevoise & Plimpton LLP for legal advice.