May 6, 2021Open Access
Preliminary Analysis of Safety and Immunogenicity of a SARS-CoV-2 Variant Vaccine Booster
View Full Paper
Ask AI
Bookmark
Share
Key result
The 50 µg mRNA-1273.351 booster increases B.1.351 neutralizing antibodies 35-fold.
- 35-fold increase from baseline
- n=40
Why the study?
Emerging SARS-CoV-2 variants with decreased susceptibility to vaccine-induced antibody neutralization and waning immunity after infection or vaccination indicated a potential need for booster vaccinations.
Does a booster dose of mRNA-1273 or mRNA-1273.351 safely increase neutralizing antibody titers against SARS-CoV-2 variants in previously vaccinated adults?
Population
Participants previously vaccinated approximately 6 months earlier with two doses of mRNA-1273
Comparison
Single 50 µg mRNA-1273 booster vs mRNA-1273.351 booster
Design
Clinical study
Follow-up
Two weeks
Authors
Discussion
Loading...
Member takes
Implication
May support variant-specific boosters in vaccinated adults; leaves open clinical protection and durability in randomized trials.
Study Design
Type
RCT (n=40)
Blinding
Open-label
Multicenter
Yes
Structured PICO
Does a booster dose of mRNA-1273 or mRNA-1273.351 safely increase neutralizing antibody titers against SARS-CoV-2 variants in previously vaccinated adults?
P
Population
40 healthy adults previously vaccinated with two doses of mRNA-1273 approximately 6 months prior, who received a single booster dose of either mRNA-1273 or mRNA-1273.351 and were evaluated for safety and immunogenicity at 2 weeks post-boost.
I
Intervention
Single booster dose of 50 µg mRNA-1273.351 (monovalent variant vaccine) or 50 µg mRNA-1273 (prototype vaccine) administered intramuscularly.
C
Comparator
The two booster groups (mRNA-1273 vs mRNA-1273.351) were compared to each other.
O
Outcome
Safety (solicited local and systemic adverse events) and immunogenicity (serum neutralizing antibody titers against wild-type and variant viruses at 2 weeks post-booster).surrogate
Main Result
Effect estimate: 35-fold increase from baseline
Absolute Event Rate: 1400% vs 864%
A single 50 µg booster dose of either mRNA-1273 or the variant-specific mRNA-1273.351 safely increased neutralizing antibody titers against SARS-CoV-2 variants, with the variant-specific booster showing greater efficacy against the B.1.351 strain.
Limitations
- Small sample size in this preliminary analysis
- Short follow-up duration of only 2 weeks post-boost
- Sequential, non-randomized enrollment for the booster cohorts
- Preliminary analysis
- Early report with only day 1 and day 15 data included
Cite This Study
Wu et al. (2021) conducted an RCT in COVID-19 (n=40). mRNA-1273.351 booster vs. mRNA-1273 booster was evaluated on Neutralizing antibody geometric mean titers (GMT) against the B.1.351 variant at 2 weeks post-boost (35-fold increase from baseline). A 50 µg booster dose of the variant-specific mRNA-1273.351 vaccine increased neutralizing antibody titers against the B.1.351 variant by 35-fold, reaching a geometric mean titer of 1400 at two weeks post-vaccination.
View Full Paper
Ask AI
Bookmark
Share