key: cord-1019389-stcdho7v
authors: Kahn, Fredrik; Shannon, Oongh; Björck, Lars
title: Thrombocytopenia with acute ischemic stroke and bleeding in a patient newly vaccinated with an adenoviral vector‐based COVID‐19 vaccine: COMMENT from Gruel et al.: RESPONSE from Kahn et al.
date: 2021-08-05
journal: J Thromb Haemost
DOI: 10.1111/jth.15467
sha: d02b5513758bc3280ca5a87d5eb26aa722a380e2
doc_id: 1019389
cord_uid: stcdho7v

We acknowledge the commentary of Gruel et al. on our recent letter [1] and are pleased that the authors agree that IdeS may be a potential treatment option for the rare but potentially severe IgG-mediated platelet activation observed in complications to vaccination with ChAdOx1 nCoV-19. It is apparent that our respective but distinct expertise with regard to IdeS has led us to develop this hypothesis in parallel. As we clearly cited in our original letter these authors have previously contributed important evidence that IdeS may be beneficial in treating IgG-mediated platelet dysfunction in a mouse model of heparin induced thrombocytopenia [2]. The intention with our letter was to provide more background to IdeS and insight into the unique properties of IdeS that make it suitable for treating many manifestations of IgG-mediated human disease.

and are pleased that the authors agree that IdeS (Imlifidase) may be a potential treatment option for the rare but potentially severe IgG-mediated platelet activation observed in complications to vaccination with ChAdOx1 nCoV-19. It is apparent that our respective but distinct expertise regarding IdeS has led us to develop this hypothesis in parallel. As we clearly cited in our original letter these authors have previously contributed important evidence that IdeS may be beneficial in treating IgG-mediated platelet dysfunction in a mouse model of heparin-induced thrombocytopenia. 2 The intention with our letter was to provide more background to IdeS and insight into the unique properties of IdeS that make it suitable for treating many manifestations of IgG-mediated human disease.

In a series of publications following our discovery of IdeS in 2001, 3 we described the specific, complete, and rapid cleavage of human IgG Therefore, in our letter we wanted to present some background to this unique and fascinating enzyme and its clinical potential to hematologists investigating this novel syndrome. Moreover, because IdeS (Ideferix) was recently approved as a drug within the EU, much due to our work for 20 years, we found it particularly important to spread this information to physicians treating these severely ill patients.

drug-related side effects and adverse reactions, IdeS, platelet factor 4, thrombocytopenia, vaccine

Dr. Kahn 

The authors have drafted and written the manuscript together.

Oongh Shannon 

Suggested treatment of serious complications to COVID-19 vaccination with IdeS, a bacterial antibody-cleaving enzyme

Cleavage of anti-PF4/ heparin IgG by a bacterial protease and potential benefit in heparininduced thrombocytopenia

IdeS, a novel streptococcal cysteine proteinase with unique specificity for immunoglobulin G

IdeS: a bacterial proteolytic enzyme with therapeutic potential