Novavax led the gains among vaccine stocks through lunchtime, as a panel of US Food and Drug Administration advisers is expected to meet today and discuss the next formula for upcoming Covid-19 shots this autumn.
"On June 5, 2024, the Vaccines and Related Biological Products Advisory Committee (VRBPAC) will meet in open session to discuss and make recommendations on the selection of the 2024- 2025 Formula for COVID-19 vaccines," the FDA wrote in a briefing document.
The FDA's new vaccine formula is expected to target the JN.1 subvariant known as KP.2, which has become dominant in the US in recent months.
Novavax's vaccine targets JN.1, which aligns with European recommendations. The EU's regulator has told pharmaceutical companies to update their vaccines for that variant.
Vaccines based on messenger RNA (mRNA), like those from Moderna or Pfizer and partner BioNTech, are also waiting for the FDA to provide formula guidance.
In the latest earnings call, Novavax executives discussed their Covid-19 vaccine targeting JN.1 went into commercial development.
"If a strain other than JN.1 is selected this late in the development process, a protein-based option will not be available for the US population," Novavax said in a statement emailed to Reuters last month. Novavax is the only company making protein-based Covid vaccines in the US.
Shares of heavily shorted Novavax soared as much as 25% on Wednesday. Shares are up more than 400% since the end of April. Data from S3 Partners shows short interest topped 33% of the equity float.
Moderna rose by as much as 5.2%, with shares up 52% for the year. BioNTech gained up to 1.8%, while Pfizer slipped slightly.