Risk of MS relapse not increased by COVID-19 vaccine, study finds

Getting the Pfizer-BioNTech vaccine for COVID-19 does not increase the risk of multiple sclerosis (MS) relapse within two months of vaccination, according to a new study.

The results support the recommendation of COVID-19 vaccines for people with MS, its researchers said.

“The incidence of relapses in the 2 months before and after vaccination was not statistically different,” the investigators wrote.

The study, “COVID-19 mRNA vaccines do not increase the short-term risk of clinical relapses in multiple sclerosis, ”Was published in the Journal of Neurology, Neurosurgery and Psychiatry.

The BNT162b2 vaccine is a messenger RNA (mRNA) vaccine for COVID-19. Simply put, it works by providing the instructions to make a piece of the SARS-CoV-2 virus – which causes COVID-19 – to cells in the body. The cells can then make that piece of virus, and the immune system “learns” to recognize that piece of virus and to defend the body against it.

In clinical trials, it has been well established that this and other COVID-19 vaccines are generally safe and can significantly reduce the risk of serious illness or death from COVID-19. However, because vaccines work by activating the immune system – and overactivity of the immune system is what causes autoimmune diseases like MS – there has been some concern about the potential safety risks of the COVID-19 vaccine. in people with such diseases.

Now, Italian researchers have reported data from 324 MS patients who received the Pfizer-BioNTech vaccine earlier this year and have been followed for at least two months.

“Our study is the first prospective study including a large cohort of patients with MS who were followed, with a self-controlled conception, for at least 2 months after the first dose of the Pfizer-BioNTech BNT162b2 vaccine,” the researchers wrote. .

Of the vaccinated patients, 28 (8.6%) had previously tested positive for SARS-CoV-2 infection. About three-quarters of the patients were women, the mean age was about 43 years, and 93.5% had relapsing-remitting MS.

All but two of the patients received both doses of the vaccine on the normal schedule, approximately three weeks apart. One patient did not receive a second dose because the individual tested positive for SARS-CoV-2 infection after the first dose, and another delayed the second dose because a pre-programmed MRI performed after the first dose revealed a possible increase in brain inflammation. .

In the two months prior to vaccination, six relapses of MS were reported in six of the patients. Within two months of vaccination, seven patients reported seven clinical relapses.

Statistical analyzes showed that the relapse rate before and after vaccination was not significantly different. No demographic or clinical characteristics showed a significant association with the risk of relapse in additional analyzes.

One limitation of the study is that regular MRI scans weren’t done, so it’s possible that some patients had brain inflammation that didn’t cause overt symptoms, scientists say. Another limitation noted is the low proportion of participants with progressive types of MS.

“Larger observational studies with longer follow-up would be desirable,” the researchers wrote.

“Despite these limitations, we believe that the results of our study may improve clinical practice by guiding clinical decisions and support the recommendation to promote access to [people with MS] vaccination against COVID-19, ”the team concluded.