SARS-CoV-2 serology in patients on biological therapy or apremilast for psoriasis: a study of 93 patients in the Italian red zone

Lombardy, Italy was one of the most heavily impacted areas in the world during the height of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, quickly becoming the epicentre within Italy. There have been 845 898 cases reported to date 19 July 2021 within Lombardy, accounting for ~20% of the cases overall in Italy.1 During the height of the pandemic, concern was raised over the use of biologics for psoriasis as they necessitate some degree of immunomodulation.2 Herein, we wish to report our real-world experience with psoriatic patients treated with biological drugs or apremilast during the SARS-CoV-2 pandemic at the tertiary level Dermatological Clinic at the IRCCS Policlinico San Matteo Foundation, Pavia, Italy. We conducted serological analysis for SARS-CoV-2 seroprevalence levels in relation to patient specific variables (including type of systemic treatment, sex, age, place of work, number of family members). We analysed present comorbidities as a factor for SARS-CoV-2 seroprevalence rates. Finally, we used the serological data to determine the usefulness of an over-the-phone questionnaire for SARS-CoV-2 positivity performed by Brazzelli et al.3 on the same cohort of psoriatic patients. All patients were over the age of 18, and under systemic therapy with biological drugs or apremilast for psoriasis. Serological data was collected from 93 psoriatic patients (n = 93) during a period from June 2020 to May 2021 using enzyme linked immunosorbent assay for SARS-CoV-2 related antibodies. Patient history was retrieved from medical records. The statistical analysis of the data was performed using Stata (Version 1.4). The study protocol was approved by the IRCCS Policlinico San Matteo Foundation, Pavia, Italy (Protocol number: 38152/2020). The parameters and variables analysed in the study are summarised in Table 1. Patients were organised into four functional groups according to the fundamental molecular target of the drug: Anti-TNF-α (Etanercept, Infliximab, Adalimumab), Anti-IL-12/23 (Ustekinumab, Guselkumab), Anti-IL-17 (Secukinumab, Ixekizumab), or Anti-PDE4 (Apremilast). In our sample cohort of 93 patients, 12 were found to have SARS-CoV-2 positivity according to anti-Spike protein IgG levels, corresponding to an incidence rate of 13%. None of the 12 positive patients had a severe infection or required hospitalisation due to SARS-CoV-2 infection. In terms of patient-specific variables, sex, age, place of work, number of family members, and type of systemic therapy did not seem to significantly alter the likelihood of having a positive SARS-CoV-2 serology. The most commonly used type of systemic therapy was Anti-TNF-α (43% of patients) which also accounted for 9/12 (75%) positive patients. Between the comorbidities analysed (Table 2), only a history of cardiovascular disease was associated with a statistically significant increase in SARS-CoV-2 seroprevalence [Odds Ratio (OR) 5.07 P-value = 0.045 (95% CI 1.03–24.8)]. Statistical analysis between serological data and over-the-phone questionnaires performed by Brazzelli et al.3 showed a strong association [OR 9.60 P-Value = 0.001 (95% CI 2.43–37.9)] between questionnaire positivity and serological positivity. In conclusion, we found an incidence rate of 13%, within the range from the literature for Italy (7.7%4–19.7%5). The use of biological drugs and apremilast for psoriasis does not seem to increase severity of the disease or susceptibility to SARS-CoV-2 infections, similar to findings from the literature.6, 7 Data from our sample cohort suggests that patients with cardiovascular disease may be at an increased risk of contracting SARS-CoV-2. Finally, over-the-phone questionnaires for SARS-CoV-2 positivity are a potentially useful diagnostic tool during the heights of pandemics where in-person meetings may not be possible. The patients in this manuscript have given written informed consent to publication of their case details. We thank the nurses Anna M. and Anna P. whose help made this study possible and our patients for their passionate collaboration. The authors have no conflicts of interest to declare. None. The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.