NEW YORK (Reuters Health) – A two-dose regimen of COVID-19 mRNA vaccines elicited a robust humoral neutralization response in almost all adolescents and young adults with childhood-onset rheumatic diseases in a new study from Singapore.
Methotrexate and mycophenolate-mofetil significantly decreased immunogenicity after the first vaccination, although not after the second dose, researchers report in Rheumatology.
No major adverse events were noted following vaccination, and the main adverse effects were self-resolving injection-site reactions with pain and swelling. Disease flare was seen in 4.4% of patients after the second mRNA vaccine dose, report Dr. Thaschawee Arkachaisri of KK Women’s and Children’s Hospital and colleagues.
“Our findings serve to reassure the community that after two vaccine doses, humoral immune response is excellent in the majority of these children,” Dr. Arkachaisri told Reuters Health by email.
He said that barring other medical concerns, children with rheumatic diseases could receive the mRNA COVID-19 vaccine if their underlying conditions are under control or show low disease activity.
The study is the first to demonstrate a robust humoral neutralization response in adolescents and young adults with childhood-onset rheumatic diseases who have completed COVID-19 mRNA vaccination, the researchers say.
The single-center observational study involved 159 participants (median age, 17, 50% female; 70% ethnic Chinese), all with inactive or low-activity disease and on stable immunosuppressive therapies. Most (57%) had juvenile idiopathic arthritis and 18% had systemic lupus erythematosus.
All participants received two doses of a mRNA COVID-19 vaccine, mostly the Pfizer-BioNTech. Humoral immune response was measured using the cPass SARS-CoV-2 Neutralization Antibody Assay.
After the first vaccination, 65% of patients mounted an adequate neutralization response, which increased to 99% after the second vaccination.
Most patients with juvenile idiopathic arthritis showed an adequate response after the first shot (64%), while this was only the case for about a third of those with systemic lupus erythematosus.
Patients receiving methotrexate or mycophenolate-mofetil were significantly less likely to achieve adequate immunogenicity after one vaccination, and this was unaffected by whether these medications were held for a week after vaccination.
Dr. Alfred H. Kim of the School of Medicine at Washington University in St. Louis, Missouri, told Reuters Health by email that these findings are consistent with those from a similar, smaller study reported in February, in that both found very high rates of seroconversion following two doses of mRNA vaccines.
He added that using the cPass assay to report neutralization titers is “an important strength of the paper.”
The relatively low seroconversion after a single dose among those receiving methotrexate or mycophenolate “highlights the need to complete the full initial series to optimize antibody responses acutely after vaccination, if tolerated,” said Dr. Kim, who was not involved in the new study.
He expressed concern, however, over what he considers the authors’ “sloppy use of terminology,” in that they used the word “efficacy.”
“Efficacy requires a formal interventional clinical study, studying those getting vaccine vs those that didn’t get vaccine,” he said
Dr. Arkachaisri countered that, “Several studies have already demonstrated that the neutralizing-antibody level is a good biomarker correlating with protection against the SARS-CoV-2 infection.”
“Clinically, there has been no severe COVID-19 infection in our patients who already received the two-dose vaccination, despite the 4% of flare, which was manageable,” he added.
SOURCE: https://bit.ly/34Fp5vF Rheumatology, online February 23, 2022.
Source: Read Full Article