Chiesi Farmaceutici, which already owned 58 percent of Cornerstone’s shares. is buying the remainder at $9.50 each in a deal that was announced Monday just before the markets opened.

The deal immediately drove down the share price of Cornerstone (Nasdaq: CRTX) from Friday’s close of $9.74.

Shares opened at $9.57 and traded as low as $9.42 in early trading.

However, that $9.50 price is 78 percent higher than on Feb. 15 when Chiesi made its initial take-private offer.

Chiesi is based in Parma, Italy. 

“Together with Chiesi, we have made significant progress in transforming Cornerstone into a market leader in our core therapeutic area of hospital and related specialty products and expect enhanced development opportunities through this exciting transaction,” said Craig Collard, CEO and chairman of Cornerstone, in a statement. “We are pleased to be able to provide employees with additional opportunities and customers with added benefits as part of a global company. Cornerstone has a solid foundation and we believe this is a natural step forward to achieve long-term success.”

The deal will boost “Chiesi’s initiative to build a larger global presence and represents a significant step towards strengthening its presence in the United States. The acquisition creates a foundation for new projects in special care and respiratory disorders and will provide a sales channel on all products Chiesi intends to commercialize in the U.S.,” the company said in the deal announcement.

Ugo Di Francesco, Chiesi’s CEO, added: ”We are excited to announce this transaction, which offers immediate and significant cash value to Cornerstone stockholders, and creates enhanced flexibility for Cornerstone to grow and prosper in the global marketplace. With the support of Chiesi, Cornerstone will help fulfill its mission to develop and commercialize innovative pharmaceutical solutions to improve the quality of human life. We will continue to promote Cornerstone’s market leading respiratory products, as we establish a strong footprint in the special care market. We look forward to working closely with the Cornerstone management team and to welcoming its talented employees to the Chiesi family.”

The deal is expected to close in the first quarter of 2014.