Are Moderna (mRNA-1273) Spikevax LP.8.1 and Pfizer (BNT162b2) vaccines safe for use?

Safety of Moderna Spikevax LP.8.1 and Pfizer COVID-19 Vaccines

Both Moderna Spikevax (mRNA-1273) and Pfizer-BioNTech (BNT162b2) COVID-19 vaccines are safe and effective for use, with the benefits significantly outweighing potential risks. 1

Safety Profile

• The Moderna and Pfizer-BioNTech COVID-19 vaccines have been thoroughly evaluated through clinical trials and post-authorization surveillance, demonstrating favorable safety profiles 1
• Both vaccines received FDA authorization and are recommended by the Advisory Committee on Immunization Practices (ACIP) for primary series vaccination 1
• The most common side effects are mild to moderate and include injection site reactions, fatigue, headache, muscle pain, chills, joint pain, and fever 1, 2

Efficacy Data

• The Pfizer-BioNTech vaccine demonstrated 95% efficacy in preventing COVID-19 in clinical trials 2
• Effectiveness against symptomatic SARS-CoV-2 infection was 87-95% for the Delta variant after two doses across vaccine products 3
• Both vaccines have shown high effectiveness against COVID-19 hospitalization and death 1, 3

Safety Monitoring

• Regular safety monitoring continues through national surveillance systems, including monitoring for rare adverse events such as myocarditis and pericarditis 1
• The risk of myocarditis and pericarditis after mRNA COVID-19 vaccination is rare, primarily observed in adolescent and young adult males 1
• The observed risk for myocarditis and pericarditis after booster doses is similar to or lower than the risk after dose 2 of the primary series 1

Special Populations

• In patients with autoimmune rheumatic diseases, the Moderna Spikevax primary series was found to be safe with no vaccine-related serious adverse events reported 4
• Vaccine effectiveness may be lower in older adults (≥60 years) compared to younger adults for most variant-vaccine combinations 3
• Immunocompromised individuals may require additional doses to achieve adequate protection 1

Recent Developments

• Bivalent booster vaccines containing components from both ancestral and Omicron strains have been authorized to improve protection against newer variants 1
• In a large Australian safety surveillance study, half (50.7%) of respondents reported any adverse event in the 0-3 days after Spikevax vaccination, with fatigue, local pain, headache, and myalgia being most common 5

Important Considerations

• The benefits of vaccination in preventing COVID-19 and its complications substantially outweigh the potential risks 1
• Vaccine effectiveness has shown some decline over time and with the emergence of new variants, which is why booster doses are recommended 1
• Comparative studies have shown that mRNA-based vaccines (Moderna and Pfizer) generally induce stronger immune responses compared to other vaccine platforms 6

Both the Moderna Spikevax and Pfizer-BioNTech COVID-19 vaccines have undergone rigorous testing and continue to be monitored for safety. The evidence strongly supports their use as safe and effective tools for preventing COVID-19 and reducing the risk of severe outcomes.