Cornerstone BioPharma is merging with Critical Therapeutics, a Massachusetts-based drug development firm, in an all-stock deal valued at around $63 million.

The combination of the two companies, which was announced after the markets closed on Thursday, will make Cornerstone a public company.

The combined firm will be called Cornerstone Therapeutics and will be based in Cary. Cornerstone currently has about 80 employees.

The deal also will add an asthma product, Zyflo-CR, to the Cornerstone product line.

"We believe this transaction will allow both companies to maximize the value of our marketed products and better exploit our commercial resources,” said Craig Collard, chief executive officer at Cornerstone. “We believe that the critical mass we aim to achieve as a specialty pharmaceutical company can enhance significantly our standing in the market.”

Collard will be the CEO of the combined company.

Critical Therapeutics stock trades on the Nasdaq with the symbol CRTX.

The deal is expected to close in the fourth quarter.