SXC Health Solutions Corp. announced today that it will buy pharmacy benefit manager Catalyst Health Solutions Inc. for about $4.4 billion in cash and stock, helping it double the number of prescription claims it handles, Reuters reported.

The pharmacy benefit management (PBM) sector’s importance has grown since the new health-care law last year heightened focus on reducing costs throughout the health-care system.

In Iowa, Catalyst has handled PBM services for the state’s dominant health insurer, Wellmark Blue Cross and Blue Shield, since 2006. Wellmark renewed its contract with Catalyst in October 2010. The Des Moines-based insurer spent $770 million on drugs in 2009, or nearly 15 cents of every premium dollar.

Last year SXC signed a string of deals in the PBM space, a market in which profits mainly come from low-cost generic medicines. The company bought privately held smaller rival HealthTrans LLC last November to boost its presence in the PBM market. This was the company’s third such deal in 2011.

Earlier this month, Express Scripts Inc. won U.S. antitrust clearance to purchase rival Medco Health Solutions Inc., following a contentious eight-month review, creating the clear leader in management of prescriptions for Americans.

SXC said that following its acquisition, it expects to have $13 billion in revenue; the company’s 2011 revenue was $5 billion.

The new company will cover about 25 million members and handle about 200 million prescriptions. It will be based in Lisle, Ill., and maintain a presence in Rockville, Md.