, as currently recommended.
“We have shown that even MS patients whose B cells were depleted from circulation with ocrelizumab can mount immune responses to COVID-19 vaccines,” said lead study author Ilya Kister, MD, of NYU Langone’s Multiple Sclerosis Comprehensive Care Center in New York.
The findings were presented at the annual meeting of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS).
VIOLA study
The data stem from VIOLA, an ongoing prospective study of humoral and cellular immune responses to COVID-19 vaccines in 60 patients with MS receiving ocrelizumab at MS care centers at NYU Langone and the University of Colorado Denver.
The mean age of participants was 38 years, 73% were women, all had been taking ocrelizumab for a mean of 1.7 years, and 45% had had COVID-19 prior to vaccination.
The researchers examined antibody and cellular responses to the two-dose series of mRNA COVID-19 vaccine (80% received the Pfizer-BioNTech vaccine, 18% the Moderna vaccine, and 2% unknown) over 24 weeks. In addition, 57% of the participants received the third dose/booster.
Results showed that antibody and cellular responses to SARS-CoV-2 spike protein significantly increased after the two-dose mRNA COVID-19 vaccination, though antibody responses tended to peak between 4 and 12 weeks and declined thereafter. There was no significant decline in cellular responses at week 24.
“The third dose ‘booster’ again significantly increased antibody and cellular responses compared with the pre–third dose levels,” Dr. Kister said.
“Importantly, cellular responses remained elevated or even increased from 4 weeks to 12 weeks after third dose/booster. Overall, these data strongly support the need for a third dose in MS patients on ocrelizumab,” Dr. Kister added.
Participants with “hybrid immunity” (those who had been infected with SARS-CoV-2 and who had also been vaccinated for COVID) had markedly higher SARS-CoV-2–specific antibody and cellular responses than those of peers with vaccine-only immunity.
CDC recs
Looking ahead, Dr. Kister said the VIOLA investigators plan to present data on the durability of COVID-19 vaccines in ocrelizumab-treated patients up to 48 weeks after the third dose.
For immunocompromised patients, such as those taking ocrelizumab, the Centers for Disease Control and Prevention considers the third dose of mRNA vaccine not as a “booster” but as part of the regular vaccine series.
“In other words, all these patients should receive three doses as part of their ‘primary’ series,” Dr. Kister noted.
The CDC also recommends receiving the updated booster for COVID-19 that became available in September 2022 (the fourth dose of the vaccine).
“Our study did not evaluate the efficacy of this fourth dose; but based on our results, it is reasonable to suppose that the fourth dose would also lead to a further increase in immune defenses,” Dr. Kister said.
The VIOLA study is an investigator-initiated collaboration supported by F. Hoffmann-La Roche Ltd/Genentech Inc. Dr. Kister has reported no relevant financial relationships.
A version of this article first appeared on Medscape.com.