Mix-and-match trial finds additional dose of COVID-19 vaccine safe, immunogenic

For adults who have previously received a complete regimen of any of the three COVID-19 vaccines approved by the Emergency Use Authorization (EUA) or Food and Drug Administration (FDA), an additional booster dose of any of these vaccines Is safe, and according to the results of preliminary clinical trials reported in, the immune response New England Journal of Medicine.. The findings served as the basis for recommendations by the FDA and the US Centers for Disease Control and Prevention in late fall 2021 to allow mixed and consistent COVID-19 booster vaccination in the United States. Additional data from the ongoing Phase 1/2 trial, sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), which is part of the National Institute of Health, is expected in the coming months.

The new report presents findings from 458 adults who were completely vaccinated with one of the three EUA COVID-19 vaccines at least 12 weeks before enrollment and had no reported history of SARS-CoV-2 infection. Explaining. At the time of enrollment, each participant received a single booster immunization. 150 people received Janssen / Johnson & Johnson’s Ad26.COV2.S. vaccination154 people were vaccinated with Moderna’s mRNA-1273 vaccine. 154 people were vaccinated with Pfizer BioNTech’s BNT162b2 vaccine. Depending on the primary vaccine regimen received by the participants, the booster vaccine was different (mixed or heterologous) or the same (matched or allogeneic) as the original vaccine.

Study participants kept a diary of side effects. More than half of the participants reported headache, injection site pain, myalgia, and malaise. No serious vaccine-related adverse events have been reported.

All combinations of the primary and booster vaccines increased neutralizing antibody levels (range 4.2-76 times higher than those detected prior to booster). Similarly, all primary booster combinations increased bound antibody levels by 4.6-56-fold. For each primary EUACOVID-19 vaccine, heterologous boosters elicited similar or higher antibody responses compared to responses to allogeneic boosters. Cellular responses (CD4 and CD8 T cells) were also increased in all but the allogeneic Ad26.CoV2.S boost group, but CD8 + T cells were at baseline in participants vaccinated with the Ad26.CoV2.SEUA vaccine. It was the highest.

In summary, the researchers concluded that “these data strongly suggest that allogeneic and heterologous booster vaccines enhance the protective effect against symptomatic SARS-CoV-2 infection.”

These interim results cover the immunogenicity data available for the first 29 days after booster immunization.Investigators will keep track of participants for a year and assess their impact. amplifier Vaccination results in a long-term immune response. An additional arm of the trial may test other ongoing EUA or FDA-approved COVID-19 vaccines and / or vaccines based on the SARS-CoV-2 variant as booster immune vaccines.

The The trial has begun Participants continue to be registered in May 2021.