In Rheumatic Disease, mRNA COVID-19 Vaccination More Likely Than J&J Shot to Generate Antibodies

By Linda Carroll

August 30, 2021

(Reuters Health) - Patients with rheumatic and musculoskeletal diseases may be less likely to mount an antibody response to the Johnson and Johnson (J&J) COVID-19 vaccine compared with those who get an mRNA-based vaccine, a new study suggests.

Data from a prospective cohort of 1,039 patients with rheumatic and musculoskeletal diseases revealed that one in five patients who received the J&J vaccine did not generate a detectable antibody response, and those who had a detectable response had lower antibody titers than patients who received an mRNA vaccine, according to the report published in the Annals of the Rheumatic Diseases.

"Patients with rheumatic and musculoskeletal diseases (RMD) who received the J&J vaccine were less likely to have a positive antibody response compared to recipients of the mRNA vaccine series," said study coauthor Dr. Caoilfhionn Connolly, a clinical fellow in the division of rheumatology at Johns Hopkins Hospital in Baltimore. A possible explanation for the different responses, she suggested, might be that these patients benefit from the second immune stimulus offered by the two-dose mRNA series.

Still, "in resource-rich settings where a choice is available between J&J or mRNA vaccination, our results suggest that patients derive more benefit from the mRNA vaccines, although additional studies are needed to further characterize these early findings," Dr. Connolly said in an email.

To explore responses to the two types of vaccine, Dr. Connolly and her colleagues turned to a cohort of patients with RMS who underwent SARS-CoV-2 vaccination between December 2020 and May 2021 with either the Pfizer/BioNTech or Moderna mRNA-based COVID-19 vaccines, or with the adenovirus-vector based J&J shot.

One month after completion of the vaccine series, the researchers performed serologic testing with the semi-quantitative Roche Elecsys anti-SARS-CoV-2 S enzyme immunoassay, which tests for antibodies against the receptor binding domain (RBD) of the SARS-CoV-2 spike (S) protein.

Dr. Connolly and her team compared anti-RBD antibody responses in the 45 patients who received the J&J vaccine to the 994 patients who received an mRNA vaccine, with adjustment for age, gender, race and use of mycophenolate, rituximab, glucocorticoid or methotrexate.

At a median of 29 days after vaccination, anti-RBD antibody was detectable in 36 of the 45 patients who received the J&J vaccine (80%) and 906 of the 994 who completed the mRNA vaccine series (92%). Median anti-RBD antibody titers in the J&J group were also lower than in the mRNA group (9.7 versus 250 U/mL).

Patients who received J&J vaccination had higher odds of negative antibody response (odds ratio 2.57) compared with those who completed the mRNA series. Consistent with prior findings, the use of rituximab, mycophenolate and glucocorticoids had a statistically significant association with negative antibody response.

The new "paper is not too surprising," said Dr. Otto Yang, a professor of medicine in the division of infectious diseases and of microbiology, immunology and molecular genetics at the David Geffen School of Medicine at the University of California, Los Angeles.

Still, "this is a very small study," Dr. Yang said. "It is suggesting that mRNA vaccines are more effective at least in making antibody responses. It's a reasonable assumption that the mRNA vaccines with do a better job of protecting these patients from infection. But that's not proven."

The paper does not look at T-cell responses, Dr. Yang said. "They are equally important for protecting people from severe disease and death," he added.

Still, in patients who are immune compromised, it's also likely their T-cell responses will be impaired, Dr. Yang said.

No hard and fast rules could yet be made because antibody responses are only part of the picture, said Dr. Nicole Bouvier, an associate professor of medicine-infectious diseases and microbiology at the Icahn School of Medicine at Mount Sinai in New York.

"From other research, we are now fairly confident in saying, at least qualitatively, that a person's antibody response to their COVID vaccination correlates pretty well with how well they'll be protected against being infected with SARS-CoV-2," Dr. Bouvier said in an email. "What we don't know a much about at this point is how important a separate arm of the immune system - called cell-mediated immunity involving T cells) is in protecting people from infection and disease. In an as-yet unpublished study of immunocompromised patients who received mRNA vaccines, cell-mediated immune responses were less blunted by immunosuppression than were antibody responses, which suggests that looking only at antibodies may make things seem worse than they really are."

SOURCE: Annals of the Rheumatic Diseases, online August 24, 2021.