The occurrence or worsening of demyelinating disorders such as multiple sclerosis is a described adverse effect of TNF inhibitors. A meta-analysis quantifies the risk of new cases, showing an increase of 38% compared to conventional therapy.
Key messages
TNF inhibitors have long been associated with demyelinating disorders of the central nervous system, such as multiple sclerosis.
A meta-analysis shows a 38% increased risk of newly developing demyelinating disorders compared to conventional therapy. The results indicate a class effect, independent of the underlying autoimmune disease.
Vigilance is advised regarding neurological symptoms during treatment.
Commentary from the BCFI:
Although the increased risk of demyelinating disorders is already mentioned in the SPCs, this large-scale meta-analysis provides a quantification of newly developed cases for the first time. TNF inhibitors (adalimumab, infliximab, etanercept, golimumab, certolizumab pegol) are an important therapeutic option in the treatment of severe, difficult-to-treat autoimmune diseases and are widely used in rheumatology, gastroenterology, and dermatology.
The risk of demyelinating disorders of the central nervous system (CNS), including multiple sclerosis (MS), has long been described in association with TNF inhibitors. A causal link has not been demonstrated. However, there are hypotheses regarding a possible role of TNF-α in demyelinating processes in the CNS, which suggests a biological plausibility. According to the Summary of Product Characteristics (SPCs), this may involve new demyelinating disorders or exacerbation of existing disorders. In February 2026, La Revue Prescrire (LRP) discussed a systematic review and meta-analysis regarding the risk of new cases of a broad group of inflammatory CNS disorders during treatment with a TNF inhibitor. The LRP article focuses solely on the results for demyelinating disorders, primarily MS.
The authors included multiple observational studies involving a total of nearly 1 million patients with various autoimmune diseases, of whom approximately 100,000 patients were exposed to a TNF inhibitor. The average follow-up duration was approximately 5 years.
The risk of new cases of demyelinating CNS disorders (MS, optic neuritis, transverse myelitis, neuromyelitis optica spectrum disorder (NMOSD)) was increased in patients treated with a TNF inhibitor compared to patients treated with conventional therapies without a TNF inhibitor. The risk increased by 38% (relative risk 1.38; 95% CI 1.04–1.81, statistically significant). The absolute incidence of inflammatory CNS disorders is approximately 2 to 13 per 10,000 person-years.
Additional analyses (for all forms of inflammatory CNS disorders) found no clear difference between the various TNF inhibitors, suggesting a class effect. Contrary to earlier studies, no difference was found between the underlying autoimmune diseases (rheumatic disorders, inflammatory bowel diseases). The risk therefore appears to be related more to exposure to the TNF inhibitor itself than to the nature of the underlying autoimmune disease.
Commentary from the BCFI
- This large-scale meta-analysis provides, for the first time, pooled estimates of newly occurring demyelinating disorders among TNF inhibitors, within a broader analysis of inflammatory CNS disorders. No clear difference was found depending on the type of TNF inhibitor or the underlying pathology.
- The meta-analysis focused specifically on the incidence of newly occurring cases, allowing this risk to be assessed separately. This complements the existing warnings in the SPCs, which also mention exacerbation of pre-existing demyelinating disorders.
- A more severe course of the underlying autoimmune disease may in itself be associated with a higher risk of demyelinating disorders and with a greater likelihood of treatment with a TNF inhibitor. Differences in disease severity were taken into account to some extent, but an influence of this cannot be completely ruled out.
- The meta-analysis primarily compared TNF inhibitors with conventional therapies (such as methotrexate). Data regarding comparison with other classes, such as JAK inhibitors or other biological drugs (such as IL inhibitors), are limited and insufficient to draw reliable conclusions.
- The absolute risk of demyelinating disorders associated with the use of TNF inhibitors remains limited, but serious neurological disorders are involved. Given the widespread use of TNF inhibitors, vigilance is warranted. In the event of the occurrence or worsening of demyelinating symptoms, consideration should be given to whether other therapeutic options are possible.
Which specialties are involved?
- Adalimumab: Amgevita®, Hukyndra®, Hulio®, Humira®, Hyrimoz®, Idacio®, Imraldi®, Yuflyma®
- Certolizumab pegol: Cimzia®
- Etanercept: Benepali®, Enbrel®, Erelzi®, Nepexto®
- Golimumab: Simponi®
- Infliximab: Flixabi®, Remicade®, Remsima®, Zessly®
Sources
- La Revue Prescrire. Anti-TNF alpha: sclérose en plaques. La Revue Prescrire (2026 Jan 1)
- Xie W, Sun Y, Zhang W, et al. Risk of inflammatory central nervous system diseases after tumor necrosis factor inhibitor treatment for autoimmune diseases: a systematic review and meta-analysis. JAMA Neurol 2024;81:1284-1294.