Pfizer-BioNTech Developing a COVID-19 Delta Variant Vaccine

Despite mounting evidence that BNT162b2 is efficacious against the Delta variant, Pfizer-BioNTech announced their plans to develop a new version of its COVID-19 vaccine that targets the rapidly circulating SARS-CoV-2 variant.

In a report Thursday afternoon, the collaborative vaccine makers—whose 2-dose mRNA product BNT162b2 was the first granted Emergency Use Authorization (EUA) for COVID-19 prevention by the US Food and Drug Administration (FDA) in December 2020—shared intention to begin clinical trials of a vaccine designed to prevent infection from the Delta variant in August.

The decision comes at a time when concerns regarding the transmissibility of the Delta variant have piqued; the variant has been identified in nearly 100 countries as of this week, and US states with lesser adult COVID-19 vaccination rates have reported weekly new case surges upwards of 50,000.

In the US, overall, new cases have increased by nearly 40% in 2 weeks.

That said, previous research has indicated that available mRNA vaccines BNT162b2 and Moderna’s mRNA-1273 have retained their approximate 90% symptomatic COVID-19 prevention efficacy against more transmissible variants.

Additionally, the FDA and Centers for Disease Control and Prevention (CDC) released a joint statement on Thursday reiterating the efficacy of full vaccination against severe COVID-19 and death, “including from the variants currently circulating in the country such as Delta.”

“Virtually all COVID-19 hospitalizations and deaths are among those who are unvaccinated,” they wrote. “Americans who have been fully vaccinated do not need a booster shot at this time.”

The statement noted the agencies, as well as the National Institutes of Health (NIH), are engaged in a “science-based, rigorous process” to consider the necessity of booster COVID-19 vaccine doses—taking into account laboratory, clinical trial, and cohort data. Though it may include data from specific pharmaceutical companies, they stressed their advisory would not exclusively rely on such reported outcomes.

“We are prepared for booster doses if and when the science demonstrates they are needed,” the statement concluded.

In accompaniment of their announced Delta variant-centric vaccine assessment, Pfizer-BioNTech reported preliminary results of a BNT162b2 booster dose assessment, showing that those who received a third dose 6 months following their second dose reported up to 10-fold improved antibodies against the original SARS-CoV-2 virus, as well as the Beta variant.