NEW YORK (CNN/Money) - Pfizer said Wednesday that it officially bought Pharmacia, creating a drug company with $46 billion in annual sales and sought-after treatments for impotence, high-cholesterol, arthritis, glaucoma and depression.

The closing of the $60 deal solidifies Pfizer's lead as the No. 1 drug maker, capping a growth-by-acquisition run for Pfizer that began three years ago with its purchase of Warner-Lambert.

The new Pfizer (PFE: Research, Estimates) isn't just the largest drug company by sales. Its $256 billion market value makes it No. 3 behind only General Electric and Microsoft. At $7 billion, its research budget also tops all rivals.

But Pfizer stock has made little progress since the deal was announced last July as investors question whether a company this big can keep growing.

The merged company will hold about 11 percent of the world's market for prescription drugs, behind Britain's GlaxoSmithKline Plc, which has a 7 percent share.

Purchased in 2000, Warner Lambert offered Lipitor, the cholesterol drug that brought Pfizer an industry record $7.9 billion in sales last years.

Pharmacia brings Rogaine for hair loss and Nicorette, the gum designed to wean smokers from cigarettes. It has a glaucoma treatment, Xalatan, an anxiety treatment, Xanax, and the leading overactive bladder treatment, Detrol.

Pharmacia fills a void of Pfizer's with Camptosar, a treatment for colorectal cancer. The acquisition will also give Pfizer control over arthritis drug Celebrex, which the companies have sold jointly since 1998. It also gives Pfizer Eplerenone, a heart disease treatment.

"On any given day, we estimate that nearly 40 million people around the world are treated with a Pfizer medicine," Pfizer's Chief Executive Officer Hank McKinnell said in statement.

Fred Hassan, Pharmacia CEO, has said he will not be joining Pfizer.

Pfizer's is the biggest deal to close since Nov. 18, 2002, when Comcast competed the purchase of AT&T's broad band unit for $72 billion, according to Thomson Financial.

The closing of the deal, announced last July, was pushed back several times as Pfizer sold a series of treatments to satisfy anti-trust regulators on both sides of the Atlantic.

New York-based Pfizer makes Zoloft, to treat depression, and the erectile dysfunction drug Viagra, the heart drug Norvasc, and over-the-counter remedies including Rolaids, Benadryl, Listerine and Sudafed.

Pharmacia shareholders get 1.4 Pfizer shares for each Pharmacia share they own. Pfizer stock fell 53 cents to $31.68 Wednesday afternoon.

Efficiencies from the deal, Pfizer said, will save $2.5 billion in 2005.

The closing of the deal brings an end to Pharmacia, which started as a Sweden-based company and merged with U.S. drugmaker Upjohn in 1995 to become Pharmacia & Upjohn. It moved its headquarters first to England and then to Peapack, New Jersey in 1998.  

-- Reuters contributed to this report