“It’s reassuring that even if you have one of the more potent inhibitors of vaccine response, you have a decent response,” says Dr. Aletaha. “We, as rheumatologists, should really try to vaccinate all our patients.”
He emphasizes that rheumatologists treat a high-risk population. Because most, if not all, immunological patients are on immunosuppressive medication and, thus, vulnerable to viremia, they should be vaccinated.
“Yes, it is very important to get these patients vaccinated,” he says.
A Third Dose?
Like patients on rituximab, solid organ transplant recipients also have an attenuated antibody response to two doses of an mRNA vaccine against SARS-CoV-2, compared with healthy controls. This finding has led the transplant community to question whether a third dose of the vaccine may benefit transplant recipients.
In June, investigators from Johns Hopkins published the first report of patients with solid organ transplants receiving a third dose of vaccine directed against SARS-CoV-2.4 The researchers examined the antibody responses and vaccine reactions in transplant recipients who had a suboptimal response to standard vaccination and, subsequently, received a third dose of vaccine a median of 67 days after the second dose. The investigators described 30 patients with a mean age of 57 in the case series. Prior to being vaccinated, none of the patients reported an illness consistent with COVID-19. The investigators tested patients for antibodies against the spike protein nine days before they received their third dose of vaccine and 14 days after the third dose of vaccine.
This study revealed that antibody titers increased after the third dose in one-third of patients who had negative antibody titers after the second dose and in all patients who had low, positive antibody titers after the second dose. The most frequent systemic reaction (seen in 14 patients) after the third dose of vaccine was mild or moderate fatigue. The study did not measure T cell responses.
Dr. Aletaha’s group has just completed the first randomized controlled trial of a third dose of COVID-19 vaccine in patients with immune-mediated diseases who did not develop antibodies after the second dose. Their manuscript has just been submitted to a journal, and Dr. Aletaha hopes it will soon be published. The bottom line: It seems a sizable number of patients can improve their immune response after a third dose of vaccine.
Consistent with these findings, on Aug. 12, the U.S. Food & Drug Administration (FDA) amended the emergency use authorizations for both the Pfizer-BioNTech COVID-19 vaccine and the Moderna COVID-19 vaccine to allow for the use of an additional dose in certain immunocompromised individuals. The amendment permits a third dose to be administered at least 28 days following the two-dose regimen of the same vaccine for individuals 18 years or older who have undergone solid organ transplantation or who are diagnosed with conditions considered to have an equivalent level of immunocompromise, including patients with rheumatic disease and cancer survivors. (For information on the ACR’s support for a third shot, read “COVID-19 Vaccination in Patients with Rheumatic Disease.”)
