Correspondence

3 Silvestre Salvador JF, Romero-Pérez D, Encabo-Durán B. Atopic dermatitis in adults: a diagnostic challenge.
J Investig Allergol Clin Immunol 2017; 27: 78–88.
4 Son JH, Chung BY, Kim HO, Park CW.
Clinical features of atopic dermatitis in adults are different according to onset.
J Korean Med Sci 2017; 32: 1360–66.
5 Kaufman BP, Guttman-Yassky E, Alexis AF. Atopic dermatitis in diverse racial and ethnic groups-variations in epidemiology, genetics, clinical presentation and treatment.
Exp Dermatol 2018; 27: 340–57.

Authors’ reply
Shelley Uppal and colleagues suggested that it cannot be concluded from our paper1 that abrocitinib is effective and well tolerated in adolescents and adults with moderate-to-severe atopic dermatitis on the basis of the limitations of the JADE MONO-1 trial. We believe our conclusions are well supported by the design and results of the study.
Regarding the diagnostic criteria, the authors commented that the Hanifin and Rajka criteria are not suitable for population-based studies. However, JADE MONO-1 was a randomised, phase 3 study that included patients with a confirmed diagnosis of atopic dermatitis. Hence, the use of these criteria, which are universally recognised as the gold standard for the clinical diagnosis of atopic dermatitis, is appropriate.2 Other diagnostic criteria for atopic dermatitis (UK working party and the American Academy of Dermatology criteria) are based on the Hanifin and Rajka criteria.2 The authors also comment that the criteria might not be suitable for adults, yet they were developed focused on adult disease and are often unsuitable for paediatric use.3 The mean age of the overall population of JADE MONO-1 was 32·5 (SD 16·0) years, and the mean duration of atopic dermatitis since onset was 23·5 (SD 15·2) years. Therefore, most patients in JADE MONO-1 had an onset of atopic dermatitis before becoming adults. No specific diagnostic biomarkers have been identified for atopic dermatitis, but we hope that changes in the future. Furthermore, in terms of the racial composition, most patients in JADE

MONO-1 were White, probably a result of the racial composition in the countries where the study sites were located. Including more Black patients in future trials will be important to fully represent the heterogeneity of atopic dermatitis. Yet, subpopulation analysis of JADE MONO-1 suggests that abrocitinib was effective in Black and White patients with atopic dermatitis. At week 12, more Black (n=32) and White (n=279) patients treated with abrocitinib (200 mg and 100 mg) versus placebo had an Investigator’s Global Assessment response (Black patients, 27·3% for 200 mg and 53·3% for 100 mg vs 0%; White patients, 45·6% for 200 mg and 16·8% for 100 mg vs 9·8%) and 75% or more improvement from baseline in the Eczema Area and Severity Index score (Black patients, 36·4% for 200 mg and 66·7% for 100 mg vs 16·7%; White patients, 64·1% for 200 mg and 32·7% for 100 mg vs 13·1%).
We believe that abrocitinib was effective and well tolerated in adults and adolescents with moderate-to- severe atopic dermatitis. Currently ongoing studies will address the efficacy and safety of abrocitinib in other populations.
ELS is a consultant for Pfizer, AbbVie, Celgene, Eli Lilly, Galderma, GlaxoSmithKline, Menlo Therapeutics,
LEO Pharma, and Regeneron; and a principal investigator for AbbVie, GlaxoSmithKline, LEO Pharma, Novartis, Regeneron, Tioga Pharmaceuticals, and Vanda Pharmaceuticals. TB is, or has been,
a lecturer or a consultant, or both, for Pfizer, AbbVie, Allmiral, AnaptysBio, Arena, Asana Biosciences, Astellas, BioVerSys, Boehringer Ingelheim, Celgene, Daichi-Sankyo, Davos Biosciences, Dermavant/ Roivant, DermTreat, DS Pharma, Evaxion, FLX Bio, Galapagos/MorphoSys, Galderma, Glenmark, GlaxoSmithKline, Incyt, Kymab, LEO Pharma, Eli Lilly, L´Oréal/LaRochePossay, Menlo Therapeutics, Novartis, Pierre Fabre, Sanofi-Regeneron, UCB,
and Vectans. JPT is an adviser, investigator, or speaker for Pfizer, AbbVie, Eli Lilly, LEO Pharma, Regeneron, and Sanofi-Genzyme. HV is an employee and shareholder of Pfizer. RR is an employee and shareholder of Pfizer. This Correspondence was funded by Pfizer, in accordance with Good Publication Practice guidelines. We thank Juan Sanchez-Cortes for editorial and medical writing support.
Eric L Simpson, Thomas Bieber, Jacob P Thyssen, Hernan Valdez,
*Ricardo Rojo
[email protected]

Oregon Health & Science University, Portland, OR, USA (ELS); Department of Dermatology and Allergy, University Hospital, Bonn, Germany (TB); Department of Dermatology and Allergy,
Herlev-Gentofte Hospital, University of Copenhagen, Hellerup, Denmark (JPT); Pfizer, New York, NY, USA (HV);and Pfizer, Groton, CT 06340, USA (RR)
1 Simpson EL, Sinclair R, Forman S, et al. Efficacy and safety of abrocitinib in adults and adolescents with moderate-to-severe atopic dermatitis (JADE MONO-1): a multicentre,
double-blind, randomised, placebo-controlled, phase 3 trial. Lancet 2020; 396: 255–66.
2 Eichenfield LF, Tom WL, Chamlin SL, et al. Guidelines of care for the management of atopic dermatitis: section 1. Diagnosis and assessment of atopic dermatitis.
J Am Acad Dermatol 2014; 70: 338–51.
3 Samochocki Z, Dejewska J. A comparison of criteria for diagnosis of atopic dermatitis in children. World J Pediatr 2012; 8: 355–58.

Using EM data to understand COVID-19 pathophysiology
The pathophysiology of multisystem inflammatory syndrome in children is not completely understood, but it Abrocitinib is a field in COVID-19 under extensive investigation. Evidence of the effects of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on extra- pulmonary tissues is essential for understanding the disease’s course and treatment.
We read with concern Carsten Dittmayer and colleagues’ Correspon- dence,1 in which they which questioned the evidence of a viral particle shown in our recent Case Report2 of a child with COVID-19-related multisystem inflammatory syndrome.
The ultrastructural evidence of SARS-CoV-2 in cardiac tissue was undisputed (a cardiomyocyte was shown in figure 3A, an endothelial cell was shown in figure 3C, and a neutrophil in figure 3D).2 This finding was further corroborated by the detection of SARS-CoV-2 RNA by RT-PCR, and by immunohistochemistry. We share Dittmayer and colleagues’1 opinion that electron microscopy (EM) is the gold standard to prove the presence of an infectious unit and requires specialised staff. For

196 www.thelancet.com Vol 397 January 16, 2021