Clinical Scorecard: Evaluation of Safety and Immune Response to mRNA Vaccine Targeting SARS-CoV-2 Spike Protein Domains
At a Glance
Category
Detail
Condition
COVID-19 caused by SARS-CoV-2 infection
Key Mechanisms
mRNA vaccines encoding receptor-binding domain (RBD) and N-terminal domain (NTD) of SARS-CoV-2 spike protein to elicit neutralizing antibody responses
Target Population
Adults aged ≥18 years previously vaccinated with mRNA-1273
Care Setting
Outpatient vaccination and clinical trial settings
Key Highlights
mRNA-1283 encodes RBD and NTD of SARS-CoV-2 spike protein, a smaller mRNA molecule than full-length spike vaccines like mRNA-1273
Phase 2a study showed mRNA-1283 and its variant formulations were well tolerated and elicited higher neutralizing antibody responses than mRNA-1273
Antibody responses remained detectable for up to one year postvaccination, supporting durable immunity
Guideline-Based Recommendations
Diagnosis
Confirm prior vaccination status with mRNA-1273 before enrollment
Monitor for SARS-CoV-2 infection by testing at baseline, day 29, 181, and 366 or if symptomatic
Management
Administer single booster dose of mRNA-1283 (2.5–10 µg), mRNA-1283.211 (5–10 µg), or mRNA-1283.529 (5–10 µg) depending on variant targeting
Store vaccines at ultralow temperatures (−90°C to −60°C for mRNA-1283 formulations) to maintain stability
Monitoring & Follow-up
Observe for reactogenicity and adverse events post-vaccination
Conduct active surveillance for breakthrough COVID-19 cases throughout follow-up
Risks
Potential reactogenicity similar to mRNA-1273 but overall well tolerated
Limited data on long-term safety beyond 12 months
Patient & Prescribing Data
Healthy adults previously vaccinated with mRNA-1273 primary series (100 µg) with or without booster
mRNA-1283 vaccines elicit higher or comparable neutralizing antibody responses at lower doses than mRNA-1273, potentially improving vaccine stability and global deployment
Clinical Best Practices
Consider mRNA-1283 as a booster option for adults previously vaccinated with mRNA-1273 to enhance immunogenicity
Use age stratification (18–55 and ≥56 years) to ensure representative safety and immunogenicity data
Maintain cold chain storage requirements to preserve vaccine integrity
Monitor antibody responses and breakthrough infections longitudinally to assess durability
by Spyros Chalkias, Antionette Pragalos, Adebayo Akinsola, Gary Berman, Madhavi Ampajwala, Jay Meyer, Lorraine Schoch, Wen Zhou, Yamuna D Paila, Weiping Deng, Jing Feng, Elizabeth de Windt, Darin Edwards, Jacqueline Miller, Rituparna Das
