Barcelona-based Grifols SA will acquire Talecris Biotherapeutics Holdings Corp. for $3.4 billion in cash and stock, expanding its U.S. market share for blood-plasma products.

Through the acquisition, Grifols gains sales of Gamunex, a treatment for three immune-system disorders, and Prolastin, the top-selling treatment for Alpha-1 antitrypsin deficiency, a condition that can lead to lung disease. The two products accounted for 77% of Talecris sales in the three months ended March 31.

Talecris chairman and chief executive officer Lawrence D. Stern commented, “We believe that Grifols’ well-established reputation, know-how and expertise will enable the combined entity to meet the needs of more patients. Our employees will benefit from the opportunities available to them as part of a larger, global organization committed to the expansion of Talecris’ existing business, the development of our pipeline products, and the maintenance of our culture of compliance and quality. Importantly, our stockholders will realize a compelling premium and benefit from the ability of the combined business to accelerate key gross margin improvement opportunities within Talecris.”

The acquisition is expected to close in 4Q10.