N Engl J Med: Abu-Raddad 2021 | Effectiveness of the BNT162b2 Covid-19 Vaccine against the B.1.1.7 and B.1.351 Variants | In a real-world test in Qatar, the BioNTech/Pfizer vaccine was 75% effective against any B.1351 infection was 75.0%, and well over 90% effective against severe, critical, or fatal disease.
1,800,000,000 BioNTech/Pfizer doses. EU Commission President Ursula von der Leyen announces a €30+ billion contract for the purchase of 900 million doses of the BioNTech/Pfizer vaccine plus an option for another 900 million doses to be delivered by 2023. The contract includes agreements to adapt the vaccine to new virus variants and to assure production in the EU, both of the vaccine and of essential components (Reuters 20210508).
WHO lists the Sinopharm vaccine for emergency use in people 18 years of age and older, giving the green light for a global roll-out (WHO 20210507). WHO’s Emergency Use Listing (EUL) is also a prerequisite for COVAX vaccine supply. At the time, the vaccine had been approved in more than 40 countries.
Immunity: Dugan 2021 | Profiling B cell immunodominance after SARS-CoV-2 infection reveals antibody evolution to non-neutralizing viral targets. | By combining B cell transcriptome, Ig sequencing, and recombinant mAb characterization, the authors found that memory B cells (MBCs) exhibited pronounced maturation to nucleoprotein (NP) and open reading frame 8 (ORF8) over time, adapting toward non-protective intracellular antigens. This phenotype was particularly pronounced in older patients who exhibited reduced MBC targeting of the spike.
medRxiv : Wu K 2021 | Preliminary Analysis of Safety and Immunogenicity of a SARS-CoV-2 Variant Vaccine Booster. | Two weeks after a booster injection to previously vaccinated individuals with either the original Moderna vaccine mRNA-1273 or the B.1.351 variant adapted mRNA-1273.351, titers against the wild-type original strain, B.1.351, and P.1 variants increased to levels similar to or higher than peak titers after the primary series vaccinations (Wu K 2021, Moderna 20210505).
One-dose version of the Gamaleya vaccine. The Russian Ministry of Health announces that ‘Sputnik Light’, a one-dose version of the Gamaleya vaccine, after an observational study found an efficacy of 79.4% (NYTimes 20200506). The vaccine is granted authorization for use in Russia.
N Engl J Med: Shiinde 2021 | Efficacy of NVX-CoV2373 Covid-19 Vaccine against the B.1.351 Variant. | Against the B.1.351variant first detected in South Africa, the Novavax nanoparticle vaccine candidate NVX-CoV2373 (not yet approved or authorized) showed 50% to 60% efficacy against the B.1.351 variant (depending on HIV serostatus).
Lancet: Haas 2021 | Impact and effectiveness of mRNA BNT162b2 vaccine against SARS-CoV-2 infections and COVID-19 cases, hospitalisations, and deaths following a nationwide vaccination campaign in Israel: an observational study using national surveillance data. | Another real-world analysis from Israel describing the impact of the BioNTech/Pfizer vaccine for 232 268 SARS-CoV-2 infections, 7694 hospitalizations, 4481 severe or critical hospitalizations, and 1113 deaths in individuals aged 16 years or older. Estimates of vaccine effectiveness at 7 days or longer after the second vaccine dose:
- 95.3% against SARS-CoV-2 infection
- 91.5% against asymptomatic SARS-CoV-2 infection
- 97.0% against symptomatic COVID-19
- 97.2% against COVID-19-related hospitalization
- 97.5% against severe or critical COVID-19-related hospitalization
- 96.7% against COVID-19-related death
The BioNTech/Pfizer vaccine for children 12-15. Canada approves the BioNTech/Pfizer vaccine for children aged 12-15 (The Guardian). Approval in the US could come as early as next week and in EU in late May or early June.
Denmark decides to not use the Johnson & Johnson vaccine.