Moderna $MRNA stock climbed as much as 20% on Friday before closing up 9.3% at $53.05, then rose an additional 7.7% in premarket trading Monday, as an unfolding hantavirus outbreak drew investor attention to the company's early-stage research on the pathogen and new clinical data on its experimental flu vaccine.
Moderna confirmed it has been conducting early-stage vaccine research on hantaviruses in collaboration with the U.S. Army Medical Research Institute of Infectious Diseases, and separately with the Vaccine Innovation Center at Korea University College of Medicine. Two separate research partnerships underpin the effort: one with the U.S. Army Medical Research Institute of Infectious Diseases and another with the Vaccine Innovation Center at Korea University College of Medicine, according to Bloomberg. "These efforts are early-stage and ongoing and reflect Moderna's broader responsibility to develop countermeasures against emerging infectious diseases," the company said in a statement.
The research predates the recent outbreak aboard the Dutch-flagged cruise ship MV Hondius. According to Medwatch, WHO has placed six infections under confirmed status and flagged two others as probable, while fatalities among those aboard the vessel have reached three.
Among the 17 American passengers being flown home after their evacuation from the ship, HHS identified one who had tested positive for the Andes strain and a second who was presenting with mild symptoms. HHS said the pair were placed in the plane's biocontainment units for the duration of the flight as a protective measure. Person-to-person spread is a trait that sets the Andes strain apart from most hantavirus varieties. While such transmission has been recorded, it is not common.
Patients diagnosed with hantavirus have no approved vaccine or targeted antiviral drug available to them; physicians can only offer supportive care.
The stock move also followed the publication of Phase 3 clinical trial results for Moderna's experimental flu vaccine, mRNA-1010, in the New England Journal of Medicine. The company said mRNA-1010 achieved the most stringent prespecified superiority criterion in the trial, with a relative vaccine efficacy of 26.6% compared to a standard-dose seasonal flu vaccine in adults 50 and older. In participants 65 and older, the relative efficacy was 27.4%.
Regulatory submissions for mRNA-1010 are under review in the U.S., Europe, Canada, and Australia, Moderna said. The company has received an FDA goal date of Aug. 5, 2026 for a decision.