Johnson & Johnson’s COVID-19 booster may be significantly more effective at warding off serious infection from the Omicron variant, according to a pair of recent studies published on Thursday.

In a company-supported study conducted by the South African Medical Research Council (SAMRC), researchers found that the Johnson & Johnson booster was able to significantly reduce hospitalization by 85% for patients who contracted Omicron.

"We observed that vaccine effectiveness for hospitalization increased over time since booster dose, from 63% to 84% and then 85%," the SAMRC team wrote in a preprint publication of their findings.

For this study, the SAMRC team focused on South African healthcare workers, who were more directly exposed to Omicron as it began to become the dominant strain in the country. Dr. Glenda Gray, president and CEO of the SAMRC, said the results of the study were "encouraging" because it demonstrated a strong case study of how effective the booster was against Omicron in a real-world setting.

Omicron was first detected in South Africa near the end of November and researchers there have conducted a number of studies into the virus’ contagiousness.

Johnson & Johnson supported a second study by researchers at Beth Israel Deaconess Medical Center in Boston to examine their booster shot and how it compared to others like Pfizer-BioNTech's.

What this team found was that the increase in antibodies in the weeks following a booster dose was similar to the levels provided by the initial dose. However, it found that the Johnson & Johnson booster increased the strength of neutralizing antibodies against the Omicron variant by 41-fold. Pfizer’s vaccine produced a smaller 17-fold increase in these antibodies.

“As the Omicron variant has mutated from the original SARS-CoV-2 strain, there is a need to understand how effective currently authorized COVID-19 vaccines remain at protecting against severe disease,” said Dan Barouch, director of the Center for Virology and Vaccine Research at BIDMC. “Our analysis shows that a booster shot of the Johnson & Johnson COVID-19 vaccine generated a robust increase in both neutralizing antibodies and T-cells to Omicron.”

These results carry some promise for the fight against Omicron, which has become the most common variant in the U.S. since it emerged.

Initially, it was found that Omicron bypassed some of the protections offered by existing vaccines. However, boosters from manufacturers, including Pfizer, were found to do a good job at protecting against serious infection.