It is believed that new Covid-19 vaccines developed by Pfizer/BioNTech, Moderna and Novavax will be effective against the fast-spreading EG.5 strain.
EG.5 or ‘Eris’ has been found in more than 50 countries. It is the most common and fastest growing Covid-19 subvariant in the US, estimated to be responsible for around 17% of current Covid-19 cases, according to the Centers for Disease Control and Prevention (CDC).
CDC data reveals that Covid-19 related hospitalisations are up more than 40% after recent lows hit in June, but are still more than 90% below peak levels hit during the January 2022 Omicron outbreak.
Focus on Omicron subvariant XBB.1.5
The new vaccine versions all target Omicron subvariant XBB.1.5, which is similar to EG.5, though the latter does contain one particular mutation that is known to evade immunity.
In June, the Food and Drug Administration (FDA) asked manufacturers to develop monovalent (single-strain) vaccines that target the Omicron XBB.1.5 subvariant.
Moderna has submitted its XBB.1.5 vaccine to both the FDA and European Medicines Agency (EMA).
“The agility of our mRNA platform has enabled us to update Spikevax, Moderna’s Covid-19 vaccine, to target XBB variants with speed and clinical rigor,” said Stéphane Bancel, CEO of Moderna. “We have been working diligently for months to build ample supply, with doses ready to ship in time for the fall vaccination season in the Northern Hemisphere. In addition, our preliminary clinical testing has demonstrated that mRNA-1273.815 is effective in generating an immune response against the current XBB variants of concern.”
New Pfizer/BioNTech and Novavax vaccines
Pfizer and BioNTech have also submitted an application for their Omicron XBB.1.5-adapted monovalent Covid-19 vaccine to the FDA and EMA, and expect to be ready to ship the adapted vaccines immediately following regulatory authorisation.
The application includes data showing that the Omicron XBB.1.5-adapted monovalent Covid-19 vaccine generates improved responses against circulating XBB sublineages, compared to the current Omicron BA.4/BA.5-adapted bivalent Covid-19 vaccine.
Novavax has announced that it “expects to be ready for the commercial delivery of a protein-based monovalent XBB Covid vaccine this fall”.
John Jacobs, President and CEO of Novavax, added: “In partnership with regulators and public health authorities, Novavax has been developing and manufacturing this vaccine candidate, and now that we are nearing harmonisation on guidance from the FDA, the World Health Organization and European Medicines Agency, we believe we are in a better position to offer an alternative vaccine choice for individuals worldwide.”
The company has demonstrated that its XBB.1.5 Covid-19 vaccine candidate induced functional immune responses for XBB.1.5, XBB.1.16 and XBB.2.3 variants, indicating a broad response that could potentially be applicable for forward-drift variants.
Diana Spencer, Senior Digital Content Editor, Drug Discovery World