Can Immunotherapy for Epstein-Barr Be a Potential MS Treatment?

Epstein-Barr virus (EBV) causes a lifelong infection and has been linked to the development of multiple sclerosis (MS) in genetically susceptible people. However, infection with EBV is extremely common. In fact, approximately 90 percent of the world's population is infected. This is because the virus is easily spread, mostly through saliva, but it can also be transmitted through other bodily fluids such as blood or semen.

Even if infected with EBV, the symptoms resemble those of other common viruses. Many people never even realize they are infected at all. There is currently no treatment to remove the virus from your body. There is also no vaccine currently available to prevent EBV infection.

Based on the strong evidence that EBV may be a culprit behind MS pathogenesis, researchers are now working tirelessly to find a treatment that targets EBV. Hopefully, this will result in the slowing down of a person's MS disease course and perhaps even prevent MS from developing in the first place.

While these goals are only emerging, very early studies are showing some promise. This includes one Australian study that examined EBV-targeted immunotherapy—a therapy that uses a person's own immune system to combat a foreign invader, like a virus or cancer.

In the Australian study in The Journal of Clinical Investigation, ten patients (five with secondary progressive MS and five with primary progressive MS) were given an adoptive T-cell therapy—a type of immunotherapy in which EBV-specific T cells from the bloodstreams of the participants are removed, regrown in a laboratory, and then infused back into their blood.

While being regrown, the T cells were stimulated to be more targeted towards the EBV virus. This way they can better attack and control the infection within the body. 

Results revealed that among the ten participants who received the targeted EBV therapy, seven showed clinical improvement, with improvements in various reported MS symptoms, such as:

• Fatigue
• Balance
• Cognitive skills (such as word-finding skills, concentration, and mental clarity)
• Mood
• Manual dexterity (improvement in handwriting)
• Urinating at night
• Leg spasticity
• Sleep
• Vision acuity
• Overall quality of life

The reduction in fatigue is one of the most commonly reported clinical improvements. This is intriguing because fatigue is one of the most prominent and disabling symptoms of both MS and acute infectious mononucleosis, also called mono—an illness caused by EBV infection.

Besides the MS symptoms listed above, it's interesting to note that three of the participants experienced a reduction in their Expanded Disability Status Scale (EDSS) score. 

On the flip side, two of the ten participants did not show any MS symptom improvement. However, they did remain stable, meaning there were no reported worsening of their MS symptoms.

Keep in mind, one participant experienced an initial MS symptom improvement but then deteriorated with an increase in their EDSS score at the end of the study. (Although, the authors of the study noted that this was "in the setting of heightened psychosocial stressors.")

Overall, the T cell therapy used in this study was well-tolerated and safe with no serious adverse events reported. In fact, the only treatment-related adverse event reported in the study was "transient dysgeusia," or impaired taste, occurring in one participant.

It's important to note that this study is a phase one trial, which is the first step in a long process to examine a new therapy. In other words, the purpose of this study (and any phase one study) is to test the waters and to determine whether this T-cell immunotherapy can be given safely without worrisome side effects.

In addition, with phase one trials, there is no control group. This means that it is difficult to determine whether any clinical improvement seen in this study was simply by chance or from actually receiving the T cell therapy.

Moreover, as the authors of the study dutifully noted, this immunotherapy is not without risk.

The thought behind this potential outcome is that the T cells may mistake EBV antigens for antigens within the brain and spinal cord (this phenomenon is called cross-reactivity).

Lastly, the potential long-term benefits of this unique immunotherapy are unclear. It's possible that as the T cell's ability to target EBV within the body dwindles, a person's MS could worsen.

Larger and more controlled trials are needed to see if EBV-specific T cell therapy is indeed an effective MS therapy. Regardless, this study is a good first step—and it serves as a motivator for those with MS to remain resilient and hopeful in their own MS journeys.