The methotrexate patients who continued therapy after the booster had significantly lower neutralization against Omicron BA.1 at both 4 weeks and 12 weeks than did their counterparts who paused therapy, as well as control patients.
The results were very similar in the same group comparisons of the serum neutralizing activity against the Omicron BA.2 variant at 4 and 12 weeks after booster vaccination.
Expert commentary
This study is noteworthy because it used SARS-CoV-2 pseudovirus neutralization assays to evaluate antibody levels, Kevin Winthrop, MD, MPH, professor of infectious disease and public health at Oregon Health & Science University, Portland, who was not involved in the study, said. “A lot of studies don’t look at neutralizing antibody titers, and that’s really what we care about,” Dr. Winthrop said. “What we want are functional antibodies that are doing something, and the only way to do that is to test them.”
Dr. Kevin Winthrop
The study is “confirmatory” of other studies that call for pausing methotrexate after vaccination, Dr. Winthrop said, including a study he coauthored, and which the German researchers cited, that found pausing methotrexate for a week or so after the influenza vaccination in RA patients improved vaccine immunogenicity. He added that the findings with the early Omicron variants are important because the newest boosters target the later Omicron variants, BA.4 and BA.5.
“The bottom line is that when someone comes in for a COVID-19 vaccination, tell them to be off of methotrexate for 7-10 days,” Dr. Winthrop said. “This is for the booster, but it raises the question: If you go out to three, four, or five vaccinations, does this matter anymore? With the flu vaccine, most people are out to 10 or 15 boosters, and we haven’t seen any significant increase in disease flares.”
The study received funding from Medac, Gilead/Galapagos, and Friends and Sponsors of Berlin Charity. Dr. Burmester reported no relevant disclosures. Dr. Winthrop is a research consultant to Pfizer.
A version of this article first appeared on Medscape.com.