Pfizer and BioNTech are asking the FDA to approve a change that would permit storage of their Covid-19 vaccine within a temperature range found in medical-grade freezers.
To be clear, this proposed change doesn’t eliminate the need for ultra-cold temperatures as the vaccine moves throughout the supply chain—temperatures that require specialized equipment. Those storage requirements are a barrier to its distribution because not all facilities have equipment that can achieve the required temperatures. What Pfizer and BioNTech are proposing is that when the vaccine reaches its destination, such as a hospital or pharmacy, it could be stored for up to two weeks at (relatively) warmer freezer temperatures.
The FDA granted emergency use authorization to the messenger RNA vaccine, named Comirnaty, last December. According to the product’s label, the vaccine must be stored in ultra-cold temperatures between minus 112 degrees and minus 76 degrees Fahrenheit (minus 80 degrees and minus 60 degrees Celsius). At those temperatures, the vaccine can last up to six months. Pfizer ships the vaccines in specially designed containers that can be refilled with dry ice every five days. Those containers can serve as temporary storage for up to 30 days.
The vaccine can be stored at refrigerator temperatures for up to five days. Pfizer and BioNTech are asking the FDA to approve an additional option to store the vaccine at minus 13 degrees to 5 degrees Fahrenheit (minus 25 degrees to minus 15 degrees Celsius) for two weeks. That range would put it closer to the storage requirements for the mRNA vaccine from Moderna. The temperature range Pfizer and BioNTech are proposing would be in addition to the five days at refrigerator temperatures that is currently permitted under the authorization.
“If approved, this new storage option would offer pharmacies and vaccination centers greater flexibility in how they manage their vaccine supply,” Pfizer CEO Albert Bourla said in a prepared statement.
Pfizer and BioNTech are proposing the additional temperature option based on new data about their vaccine’s stability. The data span from the earliest clinical trials up to batches currently in production.
Messenger RNA vaccines are a new technology that employ a snippet of genetic material from the novel coronavirus. This mRNA serve as a blueprint that a cell’s protein-making machinery use make the characteristic spike protein found on the surface of the novel coronavirus. That protein is what triggers an immune response and confers immunity.
Though mRNA vaccines are administered at room temperature, they must be kept at ultra-cold temperatures in the supply chain because mRNA is fragile. The extremely cold temperatures keep the components of the vaccine from breaking down. As mRNA companies study the storage data they have for vaccines, they are getting a better understanding of how long these vaccines can last at certain temperatures. Last November, Moderna released data that it said supported storage of its vaccine at refrigerator temperatures for up to 30 days.
Temperature requirements can be a barrier to the distribution of the vaccine to rural areas, which may not have facilities with appropriate freezers. In that regard, the Johnson & Johnson Covid-19 vaccine is seen as offering an advantage. In addition to requiring only a single shot (both authorized mRNA vaccines require two), the J&J vaccine can be stored at standard refrigerator temperatures. An FDA advisory committee is scheduled to hold a hearing about that vaccine on Feb. 26.
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