Update on antimalarials and systemic lupus erythematosus

Purpose of review The purpose of this review is highlighting the most recent evidence on the clinical efficacy and toxicity of antimalarials in systemic lupus erythematosus (SLE). Recent findings New data confirm the effects of antimalarials in preventing SLE activity, damage and infections and in decreasing mortality. An important reduction in use of health resources is related to continued antimalarial use. Hydroxychloroquine (HCQ) may prevent preeclampsia in pregnant women with SLE. HCQ ocular toxicity is infrequent and could be associated with blood levels. Gastrointestinal and skin toxicity are underrecognized and could influence adherence. Prolongation of QT interval is extremely unusual with HCQ. Doses of HCQ of 200 mg/day seem to offer a good efficacy/toxicity balance. HCQ protection against herpes zoster and Pneumocystis jirovecii infection has been shown. On the contrary, HCQ prescription by doctors and adherence by patients are both under recommended standards. The recent coronavirus disease 2019 pandemic has resulted in a significant shortage of HCQ in many countries with possible consequences in the correct treatment of lupus patients. Recent evidence reinforces the central role of HCQ in SLE therapy. The reduction in activity, damage accrual and mortality is consistent across studies, countries and ethnical groups. On the contrary, and despite the well established beneficial effects of prolonged regular HCQ therapy, many SLE patients do never take this drug or it is eventually stopped in the setting of severe flares, pregnancy or presumed toxicity. Every effort must be made to assure the correct prescription of HCQ and not to withdraw the drug unless unequivocal signs of toxicity are present.