According to a new study, the third dose of the Covid vaccine among some organ transplant recipients could help boost antibody levels who have not had robust responses to the standard vaccination schedules. Among patients in the studies who, after receiving two doses of vaccine, had no measurable antibodies, after the 3rd dose, one-third of them saw a rise in antibodies, and after two doses among those with low antibody levels, all of them saw an increase after 3rd dose. In the journal Annals of Internal Medicine, the findings were published on Monday.
Organ transplant recipients might not respond adequately to the Covid vaccine because to suppress their immune systems; they take drugs. That helps in reducing the risk of the body rejecting new organs but may also limit responses to vaccines.
According to Dr. Dorry Segev, an author of the study and founder of the Epidemiology Research Group in Organ Transplantation at Johns Hopkins University, “When it comes to Covid vaccine we don’t really have a good sense of what level you need for protective immunity. We don’t know if you need the same off-the-charts level of antibodies that people with normal immune systems have.”
Last year when pharmaceutical companies tested the Covid vaccine in a clinal trial, people who were taking immunosuppressive drugs were excluded due to potential risks. However, according to Dorry, after two doses of vaccine series for transplant patients, the majority have either no antibodies or low antibodies.
From the Johns Hopkins University School of Medicine in Baltimore, the researchers, in 30 organ transplant patients, examined vaccine reactions and antibody responses who received the 3rd dose of the Covid vaccine between March and May of this year. Nine received Moderna’s shot, six received Pfizer’s, and fifteen patients received a dose of the Johnson & Johnson vaccine around 67 days after completing the second dose of their original vaccination.
Before the 3rd dose of vaccine was given to the patients, the researcher tested for antibodies. They found 24 patients had no detectable antibodies, and 6 had low antibodies. Around two weeks after receiving the 3rd dose of vaccines, the patients were again tested for antibodies. The researchers found that the six patients who had low antibodies after the 2nd dose had a high antibody level after the 3rd dose. Among the patients with no detectable level of antibodies, 2 had a low level, 6 had a high level, and 16 remained undetectable after a third dose.
About a week later, 23 of the patients who, after the 3rd dose vaccine, completed a questionnaire about their reactions to the vaccine reported typical reactions such as muscle pain, headache, fatigue, pain at the injection site.