Merck & Co. (NYSE:MRK) fell into the red shortly after the bell Friday upon reporting second-quarter earnings less than a year ago, driven by heavy restructuring expenses associated with the drug maker’s massive merger with Schering-Plough (NYSE:SGP).

The global health company reported a profit of $752 million, or 86 cents a share, down 52% from $1.56 billion, or 83 cents a share, in the same quarter last year, though exceeding average analyst estimates of 83 cents, according to a Thomson Reuters poll.

Revenue for the Whitehouse Station, NJ-based company was $11.3 billion, up from $5.9 billion a year ago, though falling slightly below the Street’s view of $11.45 billion. Sales were driven by strong performances in its key pharmaceutical products, consumer case and animal health segments.

“Our strong bottom-line performance in the second quarter demonstrates Merck's continued success in executing our post-merger strategy," CEO Richard T. Clark said, referring to the company’s merger last year with Schering-Plough, at which time executives projected annual savings from the deal of $3.5 billion.

The company’s second quarter earnings were hit by sharp expenses related to the merger, spending $526.3 million in restructuring costs alone.

The drug maker said its “moving rapidly” to complete integration actions to achieve the savings in 2012.

The company raised its full-year non-GAAP outlook to a range of $3.29 to $3.39.