|Articles|August 25, 2021

Additional Dose of J&J COVID-19 Vaccine Supports Booster Shot

An extra dose generated a rapid and robust increase in antibodies.

Johnson & Johnson announced data this morning to support a booster dose of their COVID-19 vaccine. The booster increased antibodies nine-fold higher than 28 days after the primary single-dose vaccination.

“We have established that a single shot of our COVID-19 vaccine generates strong and robust immune responses that are durable and persistent through eight months,” Mathai Mammen, MD, PhD, global head, Janssen Research & Development, Johnson & Johnson, said. “With these new data, we also see that a booster dose of the Johnson & Johnson COVID-19 vaccine further increases antibody responses among study participants who had previously received our vaccine.”

The J&J vaccine, Ad26.COV2.S, was developed as a one-dose vaccine through its subsidiary, Janssen. The company conducted 2 phase 1/2a booster dose studies in individuals previously vaccinated with its vaccine. Significant increases in binding antibody responses were observed in participants between ages 18 and 55, and in those 65 years and older who received a lower booster dose.

In research published last month, a single-dose of the Ad26.COV2.S vaccine elicited durable humoral and cellular immune responses with minimal decreases for at least 8 months after administration.

This was an important distinction as the federal government briefed the public last week about the need for booster doses 8 months after the second dose of the mRNA vaccines, which included only the Moderna and Pfizer-BioNTech vaccines. At that time, the government agencies said they were awaiting booster data from J&J before acting on that vaccine.

Now, armed with that information, J&J is planning on submitting the data to the FDA and is speaking with the European Medicines Agency and other health authorities from other countries about booster doses.

“We look forward to discussing with public health officials a potential strategy for our Johnson & Johnson COVID-19 vaccine, boosting eight months or longer after the primary single-dose vaccination.”


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