In California, researchers from Standford University carried out a study that showed impaired response to the Johnson & Johnson attenuated adenovirus Ad26.COV2.S vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 in patients undergoing dialysis.
The researchers at Standford University evaluated the humoral vaccination response of 2,099 fully vaccinated patients undergoing dialysis.
“In partnership with a non-profit dialysis provider that serves patients undergoing dialysis in four states (California, Texas, Tennessee, and New Jersey), we evaluated the humoral vaccination response among patients receiving dialysis,” said the researchers.
Antibody response was tested in patients using the Siemen’s total receptor-binding domain (RBD) Immunoglobulin (Ig) assay that helps to measure the level of IgM and IgG antibodies.
The researchers state that the findings suggest one in three fully vaccinated patients who were undergoing dialysis showed evidence of impaired immune response to the attenuated adenovirus SARS-CoV-2 vaccine.
A pre-print version of the research paper is available on the medRxiv* server, while the article undergoes peer review.
What did the study involve?
Out of the 2,099 fully vaccinated patients selected for the study, sixty-two percent received the Moderna mRNA vaccine (mRNA1273), twenty percent took the Pfizer mRNA vaccine (BNT162b2) and eighteen percent took the Johnson & Johnson vaccine (Ad26.COV2.S).
Patients who received the attenuated adenovirus SARS-CoV-2 vaccine were younger and mostly non-Hispanic Black who received it in the South.
As mentioned above, Siemen’s RBD Ig assay was done to measure the levels of antibodies. The total RBD response was quantified using one of the two semiquantitative RBD IgG assays. Three different terminologies were applied depending on the total RBD response.
Lack of change from negative to positive was defined as “no seroconversion.” When the index value was less than one for the semiquantitative RBD IgG assay, it was defined as “no RBD IgG response.” When the index value was less than ten for the semiquantitative RBD IgG assay, it was defined as “diminished RBD IgG response.”
What did the study find?
The researchers found that whether the patient’s antibody levels were assessed during the 14-28 days window or the 28-60 days window post-vaccination, the patients receiving the attenuated adenovirus SARS-CoV-2 vaccine had a higher tendency of no seroconversion and no detectable or diminished IgG response as compared to the patients who received the mRNA vaccines.
“Patients vaccinated with BNT162b2 had a higher prevalence of no detectable or diminished IgG response, compared with patients vaccinated with mRNA1273”, says the team.
It was also found that the patients receiving home hemodialysis or peritoneal dialysis also had a higher prevalence of no seroconversion and diminished or no detectable IgG response compared to patients receiving in-center dialysis.
What did the authors conclude?
“In this large cohort of patients receiving dialysis, the prevalence of no response or diminished response to COVID-19 vaccination varied by vaccine type, with a third of patients receiving the attenuated adenovirus Ad26.COV2.S vaccine failing to seroconvert and an additional third having no detectable or diminished IgG response even 28-60 days post-vaccination”, says the team.
This study had certain limitations. It involved non-random allocation of vaccines and included patients from four states. The relationship between the immunity and the detectable serum antibody response is not always absolute, and this study was unable to test for the presence of memory B cells or cellular immunity.
“Whether additional vaccination doses or change in vaccine type are necessary for a subset of patients receiving dialysis who have failed to seroconvert or have demonstrated weak immune response in the early period post-vaccination requires further investigation”, added the team.
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.