Pfizer and BioNTech have announced they will soon be testing a SARS-CoV-2 vaccine aimed at the Delta viral variant and that they have been examining a booster dose of the original vaccine, according to the New York Times.
The companies plan to begin clinical trials of the new vaccine aimed at the spike protein of the Delta variant in August, it adds. Meanwhile, the companies say data from their tests of a booster given six months after inoculation increased antibodies against the initial viral strain and the Beta variant. In particular, they announced the booster leads to neutralization titers 5- to 10-times higher than those after the first doses. They add in their statement that the booster and new vaccine could combat declining vaccine efficacy against new viral variants like Delta.
The Times notes that while officials in Israel reported a decline in effectiveness of the Pfizer-BioNTech vaccine against the Delta variant, other analyses have concluded two doses of the vaccine is highly effective against all variants.
The US Centers for Disease Control and Prevention and the Food and Drug Administration further noted that there is no need yet for a booster dose, NPR reports. "Americans who have been fully vaccinated do not need a booster shot at this time," a joint statement from the two agencies says. "FDA, CDC, and NIH are engaged in a science-based, rigorous process to consider whether or when a booster might be necessary."