Investing.com -- Shares in Novavax (NASDAQ:NVAX) slumped in premarket US trading on Wednesday after the US Food and Drug Administration placed a trial of its experimental COVID-19 and influenza vaccine combination on hold.
The FDA's decision was due to a report of nerve damage in one person who had received the jab as part of a mid-stage trial, the firm said in a statement.
Novavax Chief Medical Officer Robert Walker noted that the group is working closely with the FDA to provide the necessary information that will the regulator to "better understand" the incident and "resolve the clinical hold" on the trial. Walker added that Novavax is aiming to start late-stage trials "as soon as possible."
"It is important to note that safety is our top priority, and while we do not believe causality has been established for this serious adverse event, we are committed to working expeditiously to fulfill requests for more information from the FDA," Walker said.
Maryland-based Novovax said figures from prior trials of the vaccine have shown no signals for nerve damage. Its protein-based COVID vaccine is its only commercial product, although it has struggled to secure market share against earlier jabs from rivals like Moderna (NASDAQ:MRNA) and Pfizer/BioNTech.
The announcement comes after Novavax inked a licensing deal worth at least $1.2 billion with Sanofi (EPA:SASY) in May. The move allowed the French drugmaker to use Novavax's COVID vaccine to develop a novel shot that would combine it with Sanofi's own flu jab.
At the time, the agreement sent Novovax's shares soaring and enabled the group to scrap a prior warning over its ability to continue operations. Shares in the company have risen by more than 102% so far this year.