Rockville-based Supernus Pharmaceuticals raised $50 million in its initial public offering on Tuesday after selling 10 million shares of the biotechnology company at $5 a piece.

Supernus develops drugs to treat central nervous system disorders, including epilepsy, attention-deficit hyperactivity disorder and depression.

The company’s shares, listed on Nasdaq under the ticker SUPN, saw a lift in their first day on the market. As of 3 p.m., the stock price had climbed 15.5 percent to $5.77.

The initial price per share marked a sharp reduction compared to the price mentioned in previous regulatory filings. Until late last month, the company had said it would sell 5.8 million shares and hoped to fetch as much as $12 or $14 a piece.

The firm declared its plans to go public in December 2010 in a Securities and Exchange Commission filing.

IPOs have not been a common exit for the region’s biotechnology community in recent years. Instead, several companies have been acquired at heft prices. .

Rockville-based Micromet was scooped up for $1.16 billion in January by Thousand Oaks, Calif.-based Amgen. In December 2010, Columbia-based Martek Biosciences sold to Netherlands-based vitamin maker Royal DSM for $1.1. billion.