NEW YORK (CNN/Money) - DOV Pharmaceutical Inc., the year's third biotech initial public offering, dropped 33 percent in its market debut on the Nasdaq Thursday.

Shares of DOV (DOVP: Research, Estimates) began trading at $12, below its $13 offer price, and kept falling. The stock closed at $8.70 Thursday, for a $4.30 loss.

DOV failed to mimic the strong showing of Ribapharm Inc., which researches antiviral and anticancer drugs. Ribapharm (RNA: Research, Estimates), a spinoff of ICN Pharmaceuticals, gained 8 percent in its market debut April 12.

Hackensack, N.J.-based DOV Pharmaceutical priced below its expected range late Wednesday, selling 5 million shares at $13 each, down from $15-to-$17, via CIBC World Markets and Lehman Brothers.

Unlike Ribapharm, DOV is an early stage drug developer and has five drug candidates on tap to treat central nervous system, cardiovascular and urological disorders. The company's most advanced drug, NBI-34060, treats insomnia and DOV has sublicensed NBI-34060 to Neurocrine Biosciences Inc.

DOV has yet to complete the development of any drug candidates and none has been approved by the Food and Drug Administration. The company also has not generated any revenue off the sale of its drugs, the company said in filing with the Securities and Exchange Commission.

Like most biotechs, DOV is not profitable, posting $5.4 million in losses on $5.7 million in revenue for the year ended Dec. 31, compared with $5.9 million in losses on no revenue for the same time period in 2000. The 7-year-old company has a total deficit of $24.5 million, DOV said in an SEC filing.