Dynavax Technologies Corp said it had withdrawn a European marketing application for its experimental hepatitis B vaccine due to safety concerns raised by the European Medicines Agency.
The EMA had said current safety data on the vaccine, Heplisav, was too limited to rule out a risk of "less common serious adverse events.
Heplisav is the company's most advanced produced under development.
The drug developer said it withdrew the application because it would not be able to gather sufficient data to respond to the regulator in the time required.
An additional 8,000-subject trial intended to provide the data is expected to begin soon, the company said.
Berkeley, California-based Dynavax suffered a similar setback in February last year when the U.S. Food and Drug Administration rejected the vaccine.
Dynavax's shares, which fell about 3 percent in early trading, were up 1.7 percent at $1.79 on the Nasdaq.
(Reporting by Natalie Grover in Bangalore; Editing by Ted Kerr)