Executive Vice President and Corporate Compliance Officer David Dockhorn of PRA Health Sciences Inc. made $4.7 million exercising stock options and then selling the stock in the open market, according to a filing with the Securities and Exchange Commission.

Dockhorn on Monday sold 55,574 shares at $62 apiece worth about $3.45 million, according to the filing. He had acquired them for the option price $2.94 a share.

Also on Monday, Dockhorn sold 29,608 shares at $62 apiece worth about $1.84 million that he acquired for the option price $11.73 a share. He still owns 85,182 shares, regulatory filings show.

Dockhorn has held several senior leadership positions at PRA, having joined in 1997 as vice president of operations and regional director of the company’s Lenexa, Kansas operations. Before joining PRA, Dockhorn worked for International Medical Technical Consultants Inc., a clinical research company acquired by PRA in 1997.

Shares of PRA closed at $64.93 Wednesday, up 0.82 percent.

The Raleigh company’s stock price has appreciated 51 percent compared to the S&P 500 average of 14 percent over the past year.

Health care was the worst performing sector in the S&P 500 last year, but was the third-best performing sector over the last five years, according to Jefferies Senior Health Care Analyst Dave Windley, speaking on “Bloomberg Markets” in January. Windley owns no stock in PRA.

On Feb. 23, the PRA reported better-than expected-earnings in the fourth quarter and projected that revenue this year will rise 14 to 16 percent.

Fourth-quarter service revenue rose to $413.6 million, up 14.2 percent, versus $405.2 million projected by analysts polled by Bloomberg News.

Adjusted net income totaled, $45.9 million, up 22.3 percent. That boosted earnings per share to 71 cents, which analyst John Kreger of William Blair & Co. noted was six cents better than consensus estimates.

Contract research organizations like PRA help pharmaceutical and biotechnology companies conduct clinical trials and analyze the results.