The week kicked off Monday with a large dose of transaction activity in the pharmaceutical industry, led by Bayer HealthCare’s announcement that it has agreed to acquire Mountain View, California–based Conceptus for $1.1 billion.

Sullivan & Cromwell is serving as Bayer’s lead legal adviser on the deal and also landed a role in a second drug-industry acquisition announced Monday: Auxilium Pharmaceuticals purchase of urology-focused drug company Actient Holdings for $585 million. The two deals were announced the same day The New York Times reported that merger talks between frequent S&C client Valeant Pharmaceuticals and Actavis had fallen apart a week after reports of a possible $13 billion deal between those two companies surfaced.

For its part, German pharmaceutical giant Bayer said Monday that its subsidiary, Bayer HealthCare, has agreed pay $31 in cash for each share of Conceptus, which manufactures nonsurgical female sterilization devices. The target company’s flagship product is Essure, a permanent birth control option that functions as an alternative to surgery. Since winning Food and Drug Administration approval in 2002, Essure has been used by more than 700,000 women, according to the deal announcement.

Bayer says that adding Essure to its current stable of contraceptive products will allow the company to offer "a complete range of short-term, long-term, and permanent contraceptive choices for women." Bayer’s current contraceptive offerings include birth control pills Yaz and Natazia, among others. (Earlier this month, sibling publication The Am Law Litigation Daily reported that Bayer’s appeal of a federal court decision that sided with three generic drug companies—including Actavis—and invalidated Bayer’s patent on Yaz.)

Latham & Watkins is advising Conceptus on the deal with a Silicon Valley–based corporate team that includes partners Michael Hall, Peter Kerman, Josh Dubofsky, and Robert Phillips. Tax partners Kirt Switzer and Grace Chen are also advising, along with benefits and compensation partner James Metz, technology transactions partner J.D. Marple, health care partner John Manthei, and capital markets partner Gregory Rodgers. Partners Karen Silverman and Joshua Holian are advising on antitrust matters. The Latham associates working on the matter are Una Au, Mark Bekheit, Julie Crisp, Elizabeth Richards, and Stephanie Wells.

Conceptus has turned to Latham in the past, including for various public share offerings and the exchange of $50 million of convertible notes in 2011. Julie Brooks serves as Conceptus’s general counsel.

In addition to S&C, Bayer has also enlisted frequent antitrust counsel Jones Day to advise on antitrust matters related to the Conceptus purchase, according to a source close to the transaction. A Jones Day spokesman did not respond to The Am Law Daily‘s request for comment.

Both S&C and Jones Day advised Bayer on its ultimately abandoned $1.2 billion offer to take over Schiff Nutrition International. Bayer and Schiff reached an agreement last October, only to see Reckitt Benckiser Group outbid the German company with a $1.4 billion offer a month later.

The S&C team advising Bayer on the Conceptus deal includes health care and life sciences group cohead Matthew Hurd, as well as intellectual property partner Nader Mousavi, tax partner Ronald Creamer, executive compensation and benefits special counsel Henrik Patel, and environmental special counsel Matthew Brennan.

Monday, it turns out, proved to a busy day for S&C, as the firm also advised Centerview Partners in its role as financial adviser to Auxilium in that company’s deal with Actient. (M&A partners Francis Aquila and Brian Hamilton are working on the matter, along with associate Marshall Yuan.)

Malvern, Pennsylvania–based Auxilium has agreed to pay $585 million in cash and a warrant for 1.25 million Auxilium shares up front—along with future considerations up to $50 million—to acquire Actient. Based in Lake Forest, Illinois, Actient makes products that include Testopel, a testosterone replacement therapy, and erectile dysfunction drugs Edex and Osbon ErecAid. The companies said the deal has been completed as of Monday and Auxilium expects to receive a tax benefit of roughly $60 million as a result of the acquisition.

Willkie Farr & Gallagher and Morgan, Lewis & Bockius are advising Auxilium on the purchase. Willkie’s team is led by corporate partner Adam Turteltaub, in New York. A Morgan Lewis team led by business transactions partner Michael Peterson and business and finance partner Patricia Brennan is advising Auxilium with respect to a $225 million secured loan the company received from Morgan Stanley Senior Funding to help finance the deal. The Morgan Lewis associates working on the matter are Tracy Dowling, Maria Emanuelli, Jonathan Frodella, Tyler Probst, Matthew Schernecke, and Lipi Shah.

Teams from Kirkland & Ellis and Hogan Lovells are advising Actient on the sale. Kirkland corporate partners Sanford "Sandy" Perl, Michael Weed, and Michael Snow are leading that firm’s Chicago-based team. Information on Hogan Lovells attorneys working on the matter was not immediately available.

Meanwhile, a tentative megadeal between Valeant and Actavis appears to be on hold. The New York Times, citing anonymous sources, reports that a potential $13 billion stock deal between the two generic drug makers has collapsed amid a variety of concerns raised by Actavis’s directors, including how big a premium above the target’s stock price Valeant was willing to pay. The Wall Street Journal, also relying on anonymous sources, reported last Friday that Valeant was in talks to buy Actavis in what would have been one of the year’s largest health care deals.

In September, S&C and Skadden, Arps, Slate, Meagher & Flom advised Valeant on its $2.6 billion purchase of skin care company Medicis Pharmaceutical Corporation. S&C also worked with Valeant on its failed $5.7 billion offer for U.S. drugmaker Cephalon in 2011, while Skadden represented the company in its $3.2 billion merger with Canada’s Biovail in 2010, with S&C advising Biovail’s board.

The Am Law Daily did not immediately receive responses from S&C and Skadden press representatives to requests for comment about whether the firms are involved in the reported talks between Valeant and Actavis.