Dynavax Technologies Corp. shares plummeted 11% after the bell Thursday on news that the Food and Drug Administration has requested more information about its post-marketing study of the company's hepatitis B vaccine. An FDA decision about the vaccine's approval is now expected by November 10. Dynavax said it plans to respond "expeditiously" to the FDA's request and that it still plans to launch the vaccine in the U.S. in early 2018. Dynavax said remaining details include timeline for the post-marketing study, timeliness of enrolling patients and an updated statistical analysis plan. Dynavax shares skyrocketed more than 70% on Monday after an FDA advisory committee voted in favor of its vaccine. The FDA has previously failed to approve Dynavax's vaccine twice. Dynavax shares have surged 330.4% over the year-to-date to $17.00, compared with a 10.4% rise in the S&P 500 .
Copyright © 2017 MarketWatch, Inc.
Continue Reading Below