Observational Study on Immunoadsorption (IA) in Patients With Autoantibody-Positive Post-Infectious ME/CFS

Overview

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a severe, often infection-triggered disease characterized by debilitating fatigue and post-exertional malaise lasting over 14 hours, along with pain, cognitive impairment, autonomic dysfunction, and sleep disturbances. Around 10% of patients after mild or moderate COVID-19 develop Post-COVID Syndrome (PCS), and some meet ME/CFS criteria after six months. No causal treatment exists for ME/CFS or PCS; current approaches are symptomatic and rehabilitative. Given the high and increasing number of affected patients, there is an urgent need for evidence-based, standardized therapies. Immunoadsorption (IA) is an established treatment for several autoimmune diseases. The first study demonstrating successful IA use in PCS-associated ME/CFS was published by our group in 2024. Earlier proof-of-concept studies (2018, 2020) in infection-related ME/CFS also showed symptomatic improvement in most patients. Hypothesis: Antibody depletion through IA improves symptoms in the majority of patients with autoantibody-positive ME/CFS and is associated with altered memory B-cell profiles before treatment. Objective: To observe and document symptom progression in 50 ME/CFS or PCS patients undergoing IA, and to examine whether changes in memory B-cells before treatment are linked to therapeutic response. The study is conducted as a non-interventional observational study. IA using the TheraSorb® column (Miltenyi) is performed within its approved clinical application.

Patients presenting to our outpatient clinic who meet the Canadian Consensus Criteria (CCC) for ME/CFS and show detectable autoantibodies are offered IA as part of routine care. Those undergoing IA are invited to participate in this observational study. Post-COVID patients fulfilling the CCC are also eligible for IA and study inclusion. IA is performed independently of the study at the Diamedikum Potsdam. The standard clinical schedule includes five outpatient sessions on days 1, 2, 4, 6, and 8. This procedure follows routine clinical practice and is not influenced by study participation. At study inclusion, all patients undergo baseline assessments including routine laboratory tests, immunoglobulins, autoantibodies, and biomarkers, with a total of 50 ml of blood collected. Additional diagnostic workup is performed as clinically indicated. The diagnosis of ME/CFS is confirmed using the CCC. Health status and symptom severity are documented using validated questionnaires: SF-36 (Physical Function subscale), work ability (past 12 months), weighted CCC symptom score, Chalder Fatigue Questionnaire, and Bell Disability Scale. These are completed monthly for 12 months after treatment. To reduce participant burden, questionnaires are mailed to patients for home completion. Further clinical and laboratory assessments are conducted before IA and at 2- and 6-months post-treatment: i) Handgrip strength, ii) NASA Lean Test, and iii) Blood sampling. The total study duration per participant is 12 months after IA. This is a non-interventional observational study following patients with ME/CFS or PCS undergoing IA using the TheraSorb® Immunoadsorption system (Miltenyi) within its approved indication. Evidence on the effectiveness of IA for ME/CFS including PCS exists only from clinical studies. This observational study aims to provide data to support a future randomized controlled trial (RCT).