BioNTech said in a regulatory filing on Tuesday the U.S. Food and Drug Administration has placed a clinical hold on an early-to-mid stage trial of its malaria vaccine.

The FDA has placed a hold on BioNTech’s phase 1/2a trial, pausing the company’s efforts to develop a RNA-based vaccine for malaria prevention. | The FDA has placed a hold on BioNTech’s phase 1/2a trial,

The vaccine space has been battered by strong headwinds in recent weeks, including high-level disruptions to FDA and CDC advisory committee meetings.