Biologic drugs during COVID-19 outbreak.

Dear Editor,

We read with interest the correspondence “Complicated coronavirus disease 2019 (COVID‐19) in a psoriatic patient treated with ixekizumab”. To improve knowledge of this important topic, we would like to describe the experience of the Dermatology Unit of a reference university hospital located in Sassari, Italy. The COVID‐19 epidemic has been causing a crisis of the national healthcare systems worldwide. The clinical management of patients has been significantly changed. The prescription of biologic therapies, which could favor SARS‐CoV‐2 infection and, then, the occurrence of a severe disease, has been a matter of debate. In Italy 214,103 cases of disease and 27,955 deaths were officially notified on May 7, 2020. Only a small proportion of patients were diagnosed in Sardinia (1,312 cases; 1,639,362 inhabitants). The psoriasis center of the University of Sassari, Sassari, Italy, followed up 1,140 patients, with 44.8% treated with systemic and biologic therapies or phototherapy. Overall, 125 (10.9%) patients, whose mean (range) age was 57 (20–82) years, were treated with TNF‐α, Il‐17, Il‐12/23, and Il‐23 inhibitors. The most prevalent comorbidities were diabetes, metabolic syndrome, obesity, cardiovascular disease, psoriatic arthritis, chronic renal failure, and IBD. Twenty‐three patients with severe atopic dermatitis were administered dupilumab; their mean (range) age was 35 (20–52) years, and their most prevalent comorbidities were asthma and allergic rhinitis. Ten patients (mean age 38 years, range: 14–54 years) were treated with adalimumab for suppurative hidradenitis. Patients were followedup through telemedicine, but severe cases were admitted to ambulatories. Patients who started biologic therapies before the occurrence of the epidemic did not interrupt their therapy, as recommended by the American Academy of Dermatology, three completed the induction phase, and two severe psoriatic patients started the biologic therapy during the epidemic. Although the prevalence of comorbidities associated with severe COVID‐19 is higher in the psoriatic population, 158 patients exposed to biologic therapies did not develop COVID‐19. Patients exposed to systemic treatment (including the small‐molecule apremilast) did not interrupt their medication course due to the infection. It is unclear if our cohort was exposed to SARS‐CoV‐2; however, our data are in line with those reported by other Italian dermatologic centers, , which highlighted the safety of biologic therapies. Furthermore, it can be hypothesized that the reduction of TNF‐α and Il‐17 can be associated with a less aggressive form of COVID‐19. A multicenter study which could enroll a larger sample could help better understand the relationship between exposure to biologic therapies and SARS‐CoV‐2 and the role played by confounding factors (e.g., age, comorbidities, and other pharmacological therapies).