Guselkumab does not appear to influence the IgG antibody response to SARS‐CoV‐2

Dear Editor, A 48-year-old gentleman was under our care for recalcitrant psoriasis since childhood. Over a 10-year period, the patient was treated with various topical and systemic agents to control his disease, including Psoralen plus ultraviolet A photochemotherapy, methotrexate, and apremilast. Unfortunately, disease remission was never achieved thus compelling him to stop all treatment between 2018 and 2019. Except for latent tuberculosis treated prior to the initiation of apremilast, the patient had no relevant medical history. The patient did not abuse of alcohol and was a nonsmoker. The cessation of systemic treatment resulted in a severe flare of disease (Psoriasis Area Severity Index 30) toward the end of 2019 for which he was referred to our dermatology tertiary center. The severity of the disease required the use of a biotherapy and the interleukin (IL)-23 inhibitor guselkumab was initiated, resulting in complete clearance of the psoriatic lesions. In December 2020, the patient and his family tested positive for the SARS-CoV-2 virus after developing mild flu-like symptoms. In view of the patient's response to treatment and mild COVID-19 symptomatology, guselkumab dose scheduling was not interrupted. Serological testing for SARS-CoV-2 carried out 4 weeks after originally testing SARS-CoV-2 PCR-positive was elevated at 20.2 UA/L (Cut off:12 UA/L). A repeat serological test conducted 6 months later was negative, confirming the development of natural immunity against SARS-CoV-2 despite the maintenance of guselkumab treatment. The patient went on to make a complete recovery from COVID-19 with no flares in his psoriasis disease activity. The use of biologic agents during, as well as for, the treatment of SARS-CoV-2 infection has been thoroughly investigated, with position statements issued by various dermatologic bodies. Treatment of SARS-CoV-2-infected psoriasis patients with guselkumab has been associated with rapid improvement of COVID-19-related dyspnea and fever. Patients receiving treatment with IL-23 inhibitors do not appear to be at an increased risk of testing positive for, being hospitalized with or dying from SARS-CoV-2 infection. With regards to SARS-CoV-2 vaccination, the American College of Rheumatologists recommends no modification in guselkumab treatment schedule in relation to SARS-CoV-2 vaccination. This is congruent with research, which indicates that neutralizing activity against wild-type SARSCoV-2 is preserved in patients on biological therapy, including IL-23 inhibitors. As observed in this case, IgG and IgM antibody kinetic undulates in response to natural infection. Current guidance by the National Psoriasis Foundation (NPF) COVID19 Task Force (version 2) recommends that “patients with psoriatic disease who become infected with SARS-CoV-2 should monitor their symptoms and discuss the management of their treatments with their health care providers. ” The NPF also notes that although the ultimate decision on psoriatic treatment in SARS-CoV-2 infected patients should be made on a case-by-case basis, it “may be prudent” to postpone treatment targeting the immune system based on “limited available data. ” The American Academy of Dermatology recommends that patients who test positive (or exhibit signs or symptoms suggestive of COVID-19) should have their biologic therapy discontinued or postponed. In conclusion, we report a patient suffering from psoriasis who had an uncomplicated SARS-CoV-2 infection with mild symptomatology and who developed natural immunity to the virus despite ongoing treatment with guselkumab. We recommend physicians consider maintaining guselkumab treatment for psoriasis in patients who test positive for SARS-CoV-2 virus and exhibit mild symptomatology. A multidisciplinary approach should be taken with regards to continuing treatment in patients with severe COVID19 symptomatology, who are likely to have their treatment stopped. The degree of immunosuppressant potential of various therapeutic agents prescribed for the management of psoriasis (targeted vs. non-targeted) should be borne in mind when altering treatment strategies in patients affected by COVID19. This case highlights the need for regularly updated, large scale, consensus guidelines on the use of biological agents in SARSCoV-2-infected patients suffering from dermatological conditions.