Forest Labs announced that it will buy Aptalis, a privately held drug maker, for $2.9 billion on Wednesday.

Aptalis produces various medications to treat cystic fibrosis and gastrointestinal disorders, according to The NY Times. In September the company had sales of $668 million. This is the biggest decision made by Forest Labs since the buy of Clinical Data in 2011. Forest plans to use money on hand and debt to make the buy.

“Aptalis is an excellent strategic and financial fit for Forest because of its strong product offerings in two therapeutic franchises that are complementary to Forest - GI in the U.S. and Canada and Cystic Fibrosis in Europe. The acquisition of Aptalis helps diversify Forest while advancing our strategy to create blockbuster therapeutic areas,”said Brent Saunders, Chief Executive Officer and President of Forest Laboratories, Inc.

According to Businessweek, Forest focuses mainly on the United States. Forest is known for medications that treat Alzheimer’s disease, irritable bowel syndrome, among various other medications. Obtaining Aptalis will expand Forest Labs into treatments for cystic fibrosis and gastrointestinal disorders.