COVID-19 Vaccines and Information for MS Patients

This information is current as of 19-January-2023

For additional information on the COVID-19 virus and the impact on patient with MS, click here.


  • Treatment for COVID-19

If you test positive for COVID-19, you may be eligible for treatment either with oral antiviral medications or an infusion. Please let your doctor know as soon as possible if you test positive as these medications need to be given with the first week of symptoms.

We advise all patients to have a low threshold to self-test in case of exposure or symptoms, and to contact your health care providers promptly for nirmatrelvir/ritonavir (Paxlovid) prescription (or mAb infusion if you have a contraindication to contraindication to Paxlovid.)  Early access to Paxlovid is likely the most effective strategy in preventing severe Covid infection. Paxlovid is a five-day oral antiviral that reduces risk of hospitalization by approximately 90 percent.

  • Evusheld Update

    We want to share updates about the new COVID variant, Omicron XBB.1.5, and Evusheld, which is a treatment to prevent COVID-19 that some of our patients who are moderately or severely immunocompromised (those on ocrelizumab, rituximab, ofatumumab, as well as fingolimod, siponimod or ozanimod) have received.

    Omicron XBB.1.5 is a novel and highly transmissible variant which is the most common subtype of virus circulating currently in New England.  Treatment of infection with nirmatrelvir-ritonavir (Paxlovid), molnupiravir, and IV remdesivir are expected to be effective against XBB.1.5. Unfortunately the majority (>97%) of circulating COVID-19 variants in New England, including the predominant Omicron XBB.1.5, are resistant to Evusheld at this time. Given Evusheld’s limited efficacy we urge you to take precautions including masking, hand washing, social distancing, and remaining up to date with vaccinations.

    We also recommend that all patients receive the updated (Bivalent booster), which has protection against the original COVID virus and the newer omicron variant. You can view more information about recommended vaccine schedule here:


    What should I do if I already have Evusheld scheduled with my next infusion?

    We expect the availability of Evusheld may change as more information becomes available. You can still get the medication as planned at this time. Given its limited efficacy, if you prefer or choose not to get it you can let your infusion nurse know when you come for your scheduled infusion.

    Will there be an updated version of Evusheld effective against circulating variants?

    We are hopeful that there will be an updated version available for the second half of 2023.


General information on the COVID-19 vaccines:

The currently approved vaccines are mRNA vaccines produced by Pfizer and Moderna, and a modified adenovirus vector virus vaccine produced by Johnson and Johnson. We do not know which vaccine you will receive. This will depend on where you live, your insurance, and other distribution factors. The Pfizer vaccine requires two doses separated by 3 weeks, the Moderna vaccine requires two doses separated by 4 weeks, and the Johnson and Johnson vaccine is a single dose vaccine.

In April 2021, distribution of the Johnson and Johnson vaccine was briefly put on hold while the CDC and FDA reviewed an extremely rare side effect of cerebral venous sinus thrombosis (a blood clot in one of the veins in the brain) associated with low platelets.  However, given the rarity of this side effect when balanced with the benefits of the vaccine, distribution of the Johnson and Johnson vaccine has now resumed.

Please contact your primary care provider immediately if you develop any of the following symptoms within one month of receiving the Johnson and Johnson vaccine.

  • Headache that is constant, worse with positional changes (bending over), or associated with nausea, vomiting, or vision changes
  • Headache that resolved within 24 hours of vaccine administration but then recurred
  • Abdominal pain, leg swelling (bilateral or unilateral), chest pain, shortness of breath, or bruising/petechiae


When should I get the vaccines? 
  • In general, we recommend that our patients follow the vaccination program guidelines developed by the Massachusetts department of public health.
  • If you are on rituximab, or ocrelizumab if possible, we would recommend getting vaccinated at least 3 months or longer after your infusion, and waiting at least 4 weeks after getting fully vaccinated before your next infusion to maximize the effectiveness. However, if this timing is not possible, then we recommend getting vaccinated whenever feasible.
    • After receiving rituximab or ocrelizumab your B cells are suppressed. B cells are a type of white blood cell important to mounting vaccine responses and providing immunity. As the rituximab or ocrelizumab wears off and your B cells start to come back, you may be more likely to mount a response to the vaccine. However, we also know that patients on B cell therapies who get COVID may be more severely affected, so the decision and timing of vaccination should be a risk/benefit discussion with your neurologist.
  • If you have had vaccine related adverse reactions, or allergic reactions please consult your primary care provider prior to getting vaccinated.
  • If you have new or worsening neurologic symptoms in the days or weeks after receiving vaccination, please, consult your neurologist.


Are the vaccines safe for patients with MS?

The vaccines were not tested in patients with MS or with other autoimmune diseases. However, inactivated vaccines such as the flu, shingles, and pneumonia vaccines are generally safe and recommended in patients with MS. The COVID-19 vaccines in the general population were found to be safe. The most common adverse effects were local pain, redness, and swelling at injection sites, as well as transient fatigue, muscle pains, joint pains, chills, or fevers. Data thus far has suggested that the COVID-19 vaccinations are safe for patients with MS and not associated with increased risk of relapse.


Are the vaccines effective for patients with MS?

The COVID-19 vaccines were not tested in patients with MS or with other autoimmune diseases. We believe that having MS will not negatively impact the efficacy of the vaccines; however, receiving some disease modifying treatments might impact overall vaccine efficacy and durability. This is an area of ongoing research. There is more information below based on what we know so far about the effectiveness of the COVID-19 vaccine and other (non-COVID-19) vaccines in MS patients on disease modifying therapies.


Will the vaccines worsen my MS?

Studies have shown no increased relapse rate after COVID vaccination. In addition, results of large trials have shown that other vaccines do not cause MS, worsen MS, or cause relapses 10,11.  It is important to note that fever can exacerbate preexisting MS symptoms but should not cause new symptoms. Please reach out to your doctor if you have persistent symptoms or new symptoms associated with the COVID vaccination.


Who can get the vaccine?

People ages 6 months and older who live, work, or study in Massachusetts can get vaccinated against COVID-19. The vaccine is safe and effective. You don’t need an ID or insurance to get it.


Table 1: Vaccine efficacy studies in patients on MS disease modifying treatments

Medication Vaccine effectiveness when compared to patients not on disease modifying therapy Further details and references
Copaxone (glatiramer acetate) As effective Patients on Copaxone receiving the flu vaccine had similar responses to healthy controls

Patients on Copaxone receiving the COVID-19 vaccine had similar responses to MS patients not on disease modifying treatments

Avonex, Betaseron, Plegridy, Rebif (interferons) As effective Patients on interferon beta-1a 44mcg three times weekly had no difference in their ability to mount an immune response to the flu vaccine compared to controls
Aubagio (teriflunomide) As effective Patients on Aubagio had similar responses to the flu vaccine compared to those on interferons.3

Tecfidera (dimethyl fumarate)

Vumerity (diroxel fumarate)

As effective Patients on Tecfidera mounted similar immune responses to pneumococcus, meningococcus and tetanus vaccines as those on interferons.4

Gilenya (fingolimod)

Mayzent (siponimod)

Zeposia (ozanimod)*

Possibly less effective Most patients on Gilenya were able to mount immune responses to the flu vaccine but response rates were less than patients not on Gilenya.5 Patients on Siponimod also had lower response rates to the flu vaccine compared to controls.6 Emerging evidence suggests that patients on these treatments may not be able to mount a full response against COVID19 after receiving a complete series of vaccinations.7,8

Tysabri (natalizumab) Possibly less effective A lower proportion of patients on Tysabri responded to tetanus vaccines compared to controls though this was not a statistically significant difference.Smaller studies have shown that fewer patients on Tysabri responded to the H1N1 vaccine10 and flu vaccine1 compared to controls.

Rituxan (rituximab)

Ocrevus (ocrelizumab)

Kesimpta (ofatumumab)*

Possibly less effective A study on tetanus, pneumococcus, and flu vaccines showed that those on Ocrevus did mount immune responses to all three vaccines, but to a lesser degree than patients not on disease modifying therapy or on interferons. Emerging evidence suggests that patients on these treatments may not be able to mount a strong response against COVID19 after receiving a complete series of vaccinations.

Mavenclad (cladribine) Unknown Two recent studies suggest that patients on Mavenclad mount successful immune response to common vaccinations:

MAGNIFY-MS study show protective antibody levels for at least six months following seasonal influenza and varicella zoster vaccines, irrespective of vaccine timing relative to cladribine dosing. Initial findings from the CLOCK-MS vaccine sub-study show protective influenza antibody levels at four weeks post-vaccination in MS patients taking Cladribine.

In both studies, protective antibody levels were maintained or increased independent of lymphocyte counts.!/9245/presentation/160!/9245/presentation/104

*No data is available for Vumerity, Zeposia or Kesimpta, but these medications are grouped with those disease modifying therapies of similar classes.