The Food and Drug Administration Monday granted Delcath Systems Inc. (DCTH) seven years of marketing exclusivity for its liver cancer treatment doxorubicin.

The news sent shares jumping 30% premarket to $3.93.

The New York-based drug developer still needs to undertake additional clinical study for the treatment, which is used in combination with Delcath's Percutaneous Hepatic Perfusion technology. It allows doctors to deliver higher doses of anti-cancer drugs to the liver without exposing the entire body to such high levels.

The orphan-drug declaration, beyond the market exclusivity, also includes some free waivers and potential tax breaks. The FDA can designate a medication as an orphan drug if the product is intended to treat a rare disease or condition affecting fewer than 200,000 patients in the U.S. a year. About 20,000 cases of primary liver cancer are diagnosed a year.

Delcath has posted a string of losses over the last year.

-By Joan E. Solsman, Dow Jones Newswires; 212-416-2291; joan.solsman@dowjones.com