Long before Pfizer's (NYSE:PFE) $68 billion bid for Wyeth put blood in the water for pharmaceutical M&A speculators, France's Sanofi-Aventis (NYSE:SNY) was emerging as a likely Big Pharma candidate to make a big deal.

At the top
The scenario starts with Chairman Jean-Francois Dehecq. He reaches the company-mandated retirement age of 70 next January and could be looking for a big score to cap his career.

He already gets credit for dozens of deals in a pharmaceutical-industry career that stretches back to 1973. Since then, he's been the top executive at Sanofi, at Sanofi-Synthelabo, and at Sanofi-Aventis, having prevailed on the board to raise the retirement age twice.

The other key player is Chris Viehbacher, who joined Sanofi-Aventis as CEO two months ago. He had been president of GlaxoSmithKline's (NYSE:GSK) North American pharmaceutical operations and was one of several executives vying to succeed Jean-Pierre Garnier, who retired as CEO last May. Viehbacher lost to another Glaxo executive, Andrew Witty.

Deal or no deal
Viehbacher makes his debut before analysts on Wednesday, when Sanofi-Aventis issues its fourth-quarter financial results. According to The Financial Times, he has told staff members that he's looking for acquisitions.

If Viehbacher embraces aggressive deal-making, that places him more in harmony with Dehecq's philosophy than former CEO Gerard Le Fur. A longtime Sanofi-Aventis research chief, Le Fur was Dehecq's handpicked replacement, but he held the job for less than two years.

Sanofi-Aventis issued a press release last September, saying that Le Fur had agreed with the board's decision to "entrust the realization of [corporate] strategy to a person able to implement it in the long term."

Trying to read between the lines, news accounts asserted that Le Fur lost the confidence of his mentor in May 2007 when they squabbled over making a takeover bid for Bristol-Myers Squibb (NYSE:BMY). According to the reports, Dehecq wanted the deal, but Le Fur didn't.

Transaction motivation
Sanofi-Aventis approaches the prospects of a big deal with a mixture of strength and urgency. The strength comes from a solid financial foundation and a $75 billion market cap. It's the sixth-largest Big Pharma company by market cap that trades on a U.S. exchange, and it is larger than any biotech company except Genentech (NYSE:DNA).

The company's strength also comes from having six drugs with more than $1 billion each in sales through the first nine months of 2008. Five of those have enjoyed double-digit sales growth compared to the same period in 2007.

Unlike at Pfizer and Eli Lilly (NYSE:LLY), where a single, aging drug counts for 25% or more of corporate revenue, Sanofi-Aventis has a balanced portfolio. Its biggest drug, the anticoagulant Lovenox, accounted for just 11% of its pharmaceutical sales for the first nine months of 2008. Moreover, Sanofi-Aventis' vaccine business rose 9.8% for the first nine months of 2008 versus last year and accounted for 10.5% of total revenue.

Better sooner than later
The urgency for making a deal comes from the fact that Sanofi-Aventis's big drugs will lose patent protection between 2011 and 2015.

The company lacks newly marketed drugs with big growth potential. Once you get past the big primary products, there isn't much driving the company because sales of the smaller, newer drugs aren't advancing quickly.

Moreover, uncertainty about the company's R&D is also putting on some pressure. The biggest blow was the failure of Acomplia, once touted as a potential source of enormous profit for treating obesity and, perhaps, smoking addiction. In June 2007, an FDA advisory panel rejected the drug. Then last October, the company halted Acomplia sales in Europe at the request of the European Medicines Agency. Two weeks later, it cancelled all clinical trials.

One last hurrah?
In recent years, Sanofi-Aventis has signed a bunch of R&D collaborations and made a handful of deals. In September, it bought British vaccine company Acambis for about $420 million. It continues pursuing Zentiva, a generic-drug company in the Czech Republic in which Sanofi-Aventis already owns about a 25% stake. The latest offer is worth about $2.4 billion. European Union antitrust regulators recently endorsed the takeover.

But these transactions lack the scope of drama of Dehecq's biggest past deal -- the $66 billion takeover of Aventis by Sanofi-Synthelabo in 2004. At the time, Sanofi-Synthelabo's revenue was half that of Aventis, and the deal drew some controversy due to worries that Novartis (NYSE:NVS) would make a competing run at Aventis.

Now, M&A rumors are revving up as drug industry-watchers speculate about the post-Pfizer-Wyeth world. For an executive who has created his share of hyphenated drug giants, the timing and environment seem right for Dehecq to make one last deal.

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Fool contributor Robert Steyer doesn't own shares in any companies mentioned in this article. Pfizer is a Motley Fool Income Investor and a Motley Fool Inside Value recommendation. Glaxo is also an Income Investor selection. The Fool owns shares of Pfizer and has a disclosure policy.