Effect of chronic hydroxychloroquine use on COVID-19 risk in patients with rheumatoid arthritis and systemic lupus erythematosus: a multicenter retrospective cohort.

Objective: Hydroxychloroquine (HCQ) has been used during the coronavirus disease 2019 (COVID-19) pandemic because of its reported anti-viral activity. This study examined the association of chronic HCQ use with the incidence and complications of COVID-19.

Methods: This retrospective cohort study included adults with rheumatoid arthritis and/or systemic lupus erythematosus who visited rheumatology clinics in three tertiary hospitals in Riyadh, Saudi Arabia between January 2019 and December 2020.

Switching treatment between mycophenolate mofetil and azathioprine in lupus patients: indications and outcomes.

Objective: To determine the reasons for changing treatment from mycophenolate mofetil (MMF) to azathioprine (AZA) or vice versa in lupus patients and to evaluate the effect of the change.

Methods: Lupus patients were identified from the University of Toronto Lupus Clinic database. Global disease activity in the 6 months prior to the change in therapy and 6 months after the change was calculated.