- New Australian study finds COVID-19 boosters improve protection for people with MS, even if they are on immune-suppressing treatments.
- Blood samples from people living with MS showed stronger antibody responses after additional doses.
- Those with some existing antibodies saw up to a four-fold boost in protection, and those with none after their earlier vaccination developed protective antibodies after boosters.
Tackling the Vaccine Challenge
People living with MS often take medicines called disease-modifying therapies (DMTs) to help manage the condition. Some of these medicines, especially those that suppress certain immune cells, can make it harder for the body to respond well to vaccines. This is important for COVID-19, as strong vaccine responses help protect against severe illness and new variants of the virus. While booster doses are known to help in the general population, it has been less clear how well boosters work for people living with MS on different treatments, and whether they improve protection against the latest variants.
What did the researchers do?
A new study supported by MS Australia and published in Neurology: Neuroimmunology & Neuroinflammation, was led by Professor Fabienne Brilot and Associate Professor Anneke Van Der Walt. The research involved 442 people living with MS across ten Australian sites and more than 1,000 blood samples.
The research team measured the level of antibodies in the blood that recognise the virus’s ‘spike’ protein, the part of the virus that vaccines target. These ‘spike antibodies’ are a key sign of immune protection and testing them can show how well someone can fight off both the original COVID-19 virus and newer variants.
The team compared results between people on different MS treatments and healthy adults. They examined whether an antibody therapy called Evusheld® offered any extra benefit. The team also developed computer modelling to predict who was likely to have strong protection and who might need another booster. In this study, the computer model was trained and tested using the spike antibody measurements alongside other information such as treatment type, age, and time since vaccination.
What did the researchers find?
The study found that a fourth vaccine dose improved the immune system’s ability to recognise and fight a wide range of COVID-19 variants in all treatment groups, even in those on strong immune-suppressing therapies. In these groups, the fourth dose increased protection two- to four-fold against newer variants and reduced the number of people with no protective antibodies by up to two-thirds.
People on lower-efficacy treatments (treatments that don’t suppress the immune system as strongly), or cladribine, generally had stronger responses from the start but still gained further benefit from boosters. Evusheld® did not provide extra protection against the variants tested compared with vaccination alone in people with living MS. The computer model predicted with high accuracy whether someone had good protection or would benefit from another booster.
What does this mean for people with MS?
These findings show that booster doses are important for people with MS, especially for those on treatments that reduce immune responses. Even if the treatment lowers antibody levels, an extra booster can still improve protection against a range of COVID-19 variants. While Evusheld® may still have some uses, it is unlikely to add meaningful extra protection against the latest variants for people living with MS. In the future, prediction tools like the one developed in this study could help personalise vaccine timing, making it easier for people living with MS to get the right protection at the right time.
