Immunoadsorption to treat patients with severe post-COVID syndrome.

Introduction: Following SARS-CoV-2-infection up to 21% of patients will develop post-COVID-syndrome. Autoantibodies (AAbs) targeting neuronal-ß-adrenergic and muscarinic receptors may provide crucial contributions to the pathophysiology of this condition. Immunoadsorption (IA) has been identified as an effective means of removing AAbs and has resulted in clinical improvements of other autoantibody-associated diseases.

Methods: We determined AAb-levels (anti-ß1/ß2 and anti-M3/M4 receptor) in 178 patients diagnosed with post-COVID-syndrome and described the clinical courses of two patients with elevated AAb-levels that underwent IA-treatment.

Results: AAbs were detected in 57% (101/178) of patients diagnosed with post-COVID-syndrome. Substantial reductions in AAb-levels and clinical remission were achieved in one of two patients who was treated with IA. However, this patient relapsed within 6 weeks with a concomitant increase in AAb-levels.

Conclusion: Collectively, AAbs may play a pathophysiologic role in post-COVID and their removal provide transient benefits in some patients. However, these findings should be further investigated in randomized-controlled-trials.