The third triMSx webinar brought together six expert speakers from four different countries and 612 registrants from 72 countries to discuss the latest data and clinical guidance on COVID-19 and multiple sclerosis (MS). The event was spread over two 1-hour sessions, and included three short presentations, three case study presentations, Q&A sessions and polling. This concise format provided convenience to time-poor researchers and clinicians who need to keep up to date with this fast-evolving area, while allowing for lively and inclusive debate.

Should we vaccinate people with MS?

Many people who are immunosuppressed, including people with MS who are receiving immunotherapies, worry about the safety of COVID-19 vaccines. Professor Ron Milo (Israel) talked about the five COVID-19 vaccines currently available. These are not live vaccines, so they cannot cause COVID-19. Israel, which is far ahead of other countries in its vaccination programme, has seen a sharp fall in new cases of COVID-19, and rates of morbidity, hospitalization and death from COVID-19. These are encouraging results, and we need to extend the success of the Israeli approach worldwide. Professor Milo then highlighted a survey of about 500 people with MS who were vaccinated against COVID-19 in Israel. The side effects of the vaccine were mostly flu-like symptoms and were similar to those seen in the general population. Importantly, there was no impact of the vaccine on MS course. The consensus was that people with MS need to be vaccinated. The results of the ambitious COVID-19 & MS Global Data Sharing Initiative, presented by Dr Liesbet Peeters (Belgium), showed that older age, progressive MS and higher disability increased the severity of COVID-19 in people with MS who get infected. Rituximab treatment, and, to a lesser extent, ocrelizumab treatment, were associated with worse COVID-19 outcomes than treatment with other disease-modifying therapies (DMTs). Notably, people with MS who are not treated with any DMT are also at increased risk of having severe COVID-19, probably because they are more likely to have progressive disease and be older than those receiving DMTs As Professor Milo said, “the way out of the pandemic is vaccination – get vaccinated if you can”.

Timing of vaccination and DMTs

The main concern about giving COVID-19 vaccines to people with MS is not safety, but rather that some DMTs can interfere with the efficacy of the vaccines. Both Professor Milo and Professor Klaus Schmierer (UK) highlighted recent data showing a blunted antibody response to the Pfizer vaccine in people with MS treated with fingolimod or ocrelizumab, while treatment with cladribine did not affect the immune response to the vaccine. These are important data that will help guide treatment decisions. Professor Schmierer presented a case study of a woman with active MS and two risk factors for COVID-19 – a high body mass index and black ethnicity. The webinar attendees were invited to consider the patient’s need for effective MS treatment and her risk of COVID-19. In a poll, 41% of the audience responded that they would start cladribine therapy and vaccinate the patient at any time (Figure 1).

In a similar case study presented by Professor Dimitrios Karussis (Israel), the attendees were asked whether a patient with MS who had started cladribine therapy should be vaccinated immediately, take the next course of cladribine immediately, or do both. In a poll, 100% of the audience said they would give the vaccine immediately and 84% said they would also continue cladribine therapy. Several of the speakers pointed out that the antibody response might not be the whole story for COVID-19 prevention. We cannot conclude from a blunted antibody response that our patients with MS do not have immunity. We need more data on T cells, memory cells and other immune system elements to understand the full picture. Professor Celia Oreja-Guevara (Spain) gave a very clear summary of current guidelines on vaccination in people with MS who are treated with different DMTs. She described the guidelines from the Barts MS Neuroimmunology group (UK), the National MS Society (USA), and Germany. All the guidelines recommend that people are fully vaccinated before receiving the first dose of a highly effective DMT. Those who are already receiving a highly effective DMT should not interrupt therapy, but there are specific intervals between their last DMT dose and vaccination that should be followed to optimise vaccination response. Even if COVID-19 vaccines may be less effective in these patients, “it’s better to have some protection than nothing”, concluded Professor Oreja-Guevara.

Vaccine hesitancy

Vaccine hesitancy is a global problem, even before the COVID-19 pandemic, and there is a lot of misinformation about COVID-19 vaccines. Therefore, it is very important that we are all familiar with the main concerns our patients may have about these vaccines. Hollie Schmidt (USA) presented a survey of more than 700 people with MS. Most of the people surveyed would want to get the vaccine, but almost half are concerned about side effects. She then shared useful tips for addressing vaccine hesitancy. For example, our patients might be more motivated to get the vaccine to protect a member of their family who cannot get it themselves because they are too ill or are immunocompromised. We should also help patients understand that some of the risks of the COVID-19 vaccines, such as the risk of blood clots, are very low. And we should also always tell them where they can find reliable information. We were reassured that, after the first day of the webinar, 97% of the attendees said they understood the interaction between COVID-19 vaccines and different DMTs well enough to make informed treatment decisions (Figure 2).

Interestingly, this percentage rose from about 50% before the meeting. As healthcare professionals, we need to have this ‘armoury’ of information on hand to be able to talk to our patients, so they too can make informed decisions about their health.

About is a virtual, free-of-charge, not-forprofit event series open to all MS researchers and healthcare professionals. Pioneered in 2018 by Gavin Giovannoni and the not-forprofit company Oxford Health Policy Forum,’s mission is to connect a diverse global audience and advance equality for all working in the field of MS. The series includes conferences, triMSx webinars and triMSAudio podcasts.

The triMSx webinar ‘COVID-19 and MS: where are we now and where next?’ is available on demand in four languages.The fifth conference ‘Making the invisible visible: the hidden symptoms of MS’ took place on 27 May 2021. Watch the conference on demand.