PRA Health Sciences, which was taken private in a $1.3 billion deal a year ago, is proceeding with plans for a return to the public markets with an IPO that could be worth as $492 million for the company, investors and the firms handling the offering.

Another Raleigh-based firm, INC Research, could go public as early as this week. 

In an updated SEC filing made on Monday, PRA said its shares could bring as much as $23 each with an expected low of $20.

The Raleigh-based life science services firm known as a contract research organization is selling nearly 17 million shares itself.

A “selling stockholder” is offering another 1.63 million shares. The remainder of the 21.4 million shares involved in the offering are options granted to the companies handling the IPO.

If the IPO is successful, PRA shares would be listed on the Nasdaq under the symbol “PRAH.”

“This is our initial public offering, and no public market currently exists for our shares,” PRA said in the filing. We anticipate that the initial public offering price will be between $20.00 and $23.00 per share. We have applied to have our common stock listed on the NASDAQ Global Select Market under the symbol PRAH.”

Jefferies, Citigroup, KKR, UBS Investment Bank, Credit Suisse, Wells Fargo Securitie,s Baird, and William Blair will handle the offering.

Last September, PRA merged with Pennsylvania clinical research organization ReSearch Pharmaceutical Services, forming what the combined company says is now the fourth largest CRO in the industry.

Raleigh-based PRA closed on the deal nearly two months after announcing the plan to join the two companies to form a larger, global company running clinical trials and providing other services to pharmaceutical companies.

RPS operates as PRA’s Strategic Solutions Division. The combined company is led by PRA CEO Colin Shannon.

The merger was the second major transaction for PRA. In June private equity firm KKR acquired PRA. No purchase price was disclosed but Bloomberg News, citing an unidentified person familiar with the matter, reported at the time that the price was $1.3 billion. The acquisition followed PRA’s confidential filing of plans for an initial public stock offering.

PRA says that since 2000, the CRO has performed roughly 2,000 clinical trials in more than 80 countries for more than 300 clients. RPS has an established presence in North America and Europe, the Middle East and Africa along with specialized capabilities in Latin America and Asia. The company brings to PRA its 4,000 employees in more than 64 countries. The combined company will have nearly 10,000 employees globally.

Last November, PRA acquired a 250-employee research firm.

The filing can be read online.