What type of COVID-19 booster dose you get later this year depends on where you live.
Vaccine maker Moderna is preparing two omicron-targeting boosters for different countries. If the company’s plans come to fruition, it would mark the first time that COVID-19 vaccines would target different versions of the pandemic coronavirus in different locations. So far, all vaccines, including the booster, have targeted the parental strain of SARS-CoV-2, which was first identified in Wuhan, China.
Moderna’s next-gen boosters are both candidate bivalent vaccines, targeting both the parental virus and some variant of Omicron. A booster option targets BA.1 – Omicron’s version that first rolled out of South Africa last November, causing a major wave of infections in the US in January 2022. That BA.1-based next-gen booster could be available in the EU, UK, Australia and elsewhere later this month or as early as August. Moderna’s other booster option targets BA.4/5 and is intended for use in the US. However, it probably won’t be ready until early mid-fall.
The US division follows guidance from the US Food and Drug Administration, which late last month specifically advised vaccine manufacturers to develop bivalent vaccines targeting BA.4/5. The regulator based its recommendation on the feedback of a committee of expert advisors. The committee voted 19 to 2 in favor of updating the Fall Booster to target some variant of Omicron, with the advisors informally agreeing that the booster should be bivalent and targeting BA.4/5.
BA.4 and BA.5, which share similar spike protein mutations, are gaining dominance worldwide. In the US, BA.5 now accounts for an estimated 54 percent of infections, according to the Centers for Disease Control and Prevention. With BA.1 no longer operating in the US, consultants felt that a BA.4/5-targeted vaccine would provide the best boost of protection for the fall.
Trouble is, Moderna and the other major vaccine makers, Pfizer and BioNTech, had no clinical data on the effectiveness of BA.4/5-targeting vaccines. Both focused on BA.1-based vaccines.
Today, in announcing its two-pronged booster plans, Moderna released the first top-line data showing that its BA.1-targeting bivalent vaccine (mRNA-1273.214) performed better than BA.4 and BA.5. In protection against current the booster has better performance. Specifically, the company reported that in participants without prior SARS-CoV-2 infection, the mRNA-1273.214 booster generated approximately 70 percent higher neutralizing titers to BA.4/5 than the currently authorized booster. Compared with pre-booster antibody levels, the geometric mean fold increase in BA.4/5 antibody increased 6.3-fold among mRNA-1273.214 recipients, but only 3.5-fold for mRNA-1273 recipients.
“Today’s update extends the remarkable performance of mRNA-1273.214, demonstrates significantly higher titers than all tested variants, including the ba.4/5 and ba.1 omicron subvariants, and adds to the largest body of data.” “This improved breadth and durability of the immune response following a bivalent booster is now available in several Phase 2/3 studies involving thousands of participants,” Moderna CEO Stefan Bansell said in a statement. shown in.”
It is not clear whether a bivalent booster that specifically targets BA.4/5 would overtake that, and—if it does—to what extent. This question may be important because development of a BA.4/5-targeting booster could push back the rollout of next-generation booster doses in the US by months—potentially beyond the point where BA.4/5 is effective in the US. Is. , While BA.5 is now widespread in the US, researchers are already closely monitoring a new Omicron subvariant, BA.2.75.
Nevertheless, Moderna is also working on a BA.4/5-based booster, dubbed mRNA-1273.222. Its dual booster plans are “based on the different market preferences for Omicron subvariants, clinical data requirements, and the urgency of launching a fall booster campaign for vulnerable populations,” Bansel said.
Meanwhile, Pfizer has also said that Following the recommendation of the FDA and developing a BA.4/5-targeting booster to be used this fall in the US.