Spikevax Moderna’s latest COVID vaccine outperforms the current shot in a crucial efficacy trial involving adults.

Spikevax Moderna latest COVID vaccine announced on Thursday that its upcoming COVID-19 vaccine showed higher effectiveness in adults during a Phase III trial compared to its current Spikevax vaccine.

Spikevax, mRNA-1283: Moderna latest COVID vaccine

Spikevax, which is Moderna’s authorized COVID-19 vaccine, utilizes mRNA technology to encode the full-length SARS-CoV-2 S protein. Initially, Spikevax demonstrated 94.5% efficacy in its pivotal trial back in 2020. However, real-world usage highlighted opportunities to enhance Spikevax’s effectiveness, particularly against emerging variants, and to streamline logistical aspects. The next-generation vaccine, mRNA-1283, represents Moderna’s efforts to address these improvements.

In contrast to Spikevax, mRNA-1283 encodes two segments of the S protein that include critical SARS-CoV-2 neutralization epitopes—the N-terminal domain and receptor binding domain. Jacqueline Miller, Moderna’s senior vice president of infectious disease development, elaborated on this design rationale during the biotech company’s vaccine day in March 2024.

Miller emphasized that the most potent antibodies target both the receptor binding domain and the N-terminal domain. He suggested that this breakthrough could facilitate the development of combination vaccines by minimizing interference with adapted antigens, potentially making their COVID-19 vaccine more competitive.

Moderna announced that mRNA-1283 elicited a stronger immune response than Spikevax in a Phase III trial conducted in March. The latest data illustrates how this heightened immune response translated into protection against COVID-19.

In the study involving 11,400 participants aged 12 and older, the investigational vaccine demonstrated non-inferior efficacy to Spikevax overall and showed superior efficacy in adults compared to the first-generation vaccine. Moderna noted a consistent positive trend among adults aged 65 and older, with the highest antibody levels observed in this demographic when the immune response data was released in March.

Moderna’s mRNA-1283 candidate demonstrated comparable or superior efficacy to Spikevax, despite being administered at a lower dose of 10μg compared to Spikevax’s 50μg. According to Moderna, the shorter mRNA sequence of mRNA-1283 enables higher levels of protein expression at similar or lower doses than Spikevax. Additionally, the design of mRNA-1283 may allow for extended refrigerated storage periods.

In the latest study, mRNA-1283 showed a safety profile similar to Spikevax, with common solicited side effects including injection site pain, fatigue, headache, and muscle aches. Moderna intends to engage with regulators to discuss the next steps for advancing the program.

Recently, Moderna announced an update following its Phase III data release on a combined COVID-19 and influenza vaccine. This innovative vaccine integrates Moderna’s next-generation COVID-19 vaccine, designed to minimize interference with the adapted antigen. Results indicate that Moderna’s combination vaccine elicited stronger immune responses against both COVID-19 and influenza compared to currently licensed products.

Moderna’s development of a combined COVID-19 and influenza vaccine marks a significant advancement in pandemic preparedness and vaccine technology. The company’s approach leverages its expertise in mRNA technology to create a dual-purpose vaccine that targets both COVID-19 and seasonal influenza viruses.

The decision to combine these vaccines arises from Moderna’s research, which demonstrates that the next-generation COVID-19 vaccine can be effectively integrated without compromising efficacy against either virus. This is crucial as it addresses concerns about potential interference between vaccines targeting different pathogens.

In Phase III trials, Moderna reported promising results showing superior immune responses compared to currently licensed products for both COVID-19 and influenza. This includes enhanced antibody production and robust T-cell responses, which are pivotal in providing broad protection against viral infections.

The development of such a combination vaccine not only streamlines vaccination efforts but also offers potential benefits in terms of convenience and efficiency. By reducing the number of injections needed and possibly enhancing overall immune response, Moderna’s initiative could redefine preventive strategies against respiratory viruses in the future.

Furthermore, Moderna’s proactive approach in integrating cutting-edge research into vaccine development underscores its commitment to combating infectious diseases on multiple fronts. This innovative approach not only addresses current public health challenges but also prepares for potential future outbreaks more comprehensively.