Of 436 solid organ recipients who received their first dose of the COVID-19 vaccine, antibodies were detected in 76 participants, according to a research letter published March 15 in JAMA.
Because immunocompromised people were not included in messenger RNA vaccine trials, researchers set out to capture vaccine response among organ transplant recipients.
They recruited 436 participants across the U.S. who received their first COVID-19 shot between Dec. 16, 2020, and Feb. 5, 2021. None of the participants had a previous confirmed COVID-19 infection.
A median of 20 days after receiving the vaccine, 17 percent of participants developed a positive antibody response, according to the study. Researchers noted that participants receiving anti-metabolite maintenance immunosuppression therapy were less likely to develop an antibody response than those who were not on such therapy. Older transplant recipients were also less likely to have a detectable immune response.
"These findings of poor antispike antibody responses in organ transplant recipients after the first dose of mRNA vaccines suggest that such patients may remain at higher early risk for COVID-19 despite vaccination," the report said. "Deeper immunophenotyping of transplant recipients after vaccination, including characterization of memory B-cell and T-cell responses, will be important in determining vaccination strategies as well as immunologic responses after the second dose."
To view the full report, click here.