Rituximab Might Benefit Some Patients With Severe COVID-19

By Will Boggs MD

August 14, 2020

NEW YORK (Reuters Health) - B-cell depletion with rituximab might benefit certain some patients with severe COVID-19, researchers in the UK say.

Rituximab is used to treat patients with severe, refractory rheumatic disease. Some registry evidence suggests the drug does not worsen outcomes in patients with COVID-19, but a severe COVID-19 phenotype has been reported in a patient treated with rituximab for antineutrophil cytoplasmic antibody-associated vasculitis.

In a report in The Lancet Rheumatology, Dr. Venkat Reddy and colleagues at University College London discuss the current knowledge about B-cell-mediated adaptive immunity and rituximab with regard to safety and the potential to treat specific COVID-19 complications.

B-cell depletion could compromise antiviral immunity, increase the risk of reinfection with SARS-CoV-2, and impair efficacy of whatever vaccine is developed.

On the other hand, rituximab might be useful for targeting such chronic adaptive host immune responses as COVID-19-associated thrombosis or inflammatory lung complications that persist beyond acute infection and when viral loads are negative or low and anti-SARS-CoV-2 antibodies are positive.

To address these issues, the authors "call for dedicated research regarding B-cell depletion to better understand the effect and timing of rituximab on patient outcomes and to explore its potential therapeutic use in the management of specific complications of COVID-19, to determine whether judicious use of rituximab might have a role in the pandemic."

Dr. Ulrich A. Walker of University Hospital Basel, in Switzerland, who recently reported a mild course of COVID-19 in a patient treated with rituximab, told Reuters Health by email, "I think that current data warrant the use of rituximab on a case-by-case basis. Certainly rituximab is an important drug for patients with active granulomatosis with polyangiitis, and its alternatives (high-dose glucocorticosteroids and cyclophosphamide) are likely to not only severely compromise humoral but also cellular immunity."

"At present, I do not see an absolute contraindication, but the use of rituximab may be deferred in quiescent disease," he said.

"The main message so far is that we need more data," Dr. Walker said. "This should encourage physicians to enter treatment data into registries and also encourage political decision makers to encourage physicians to do so."

Dr. Reddy reports receiving funding from Roche, which markets rituximab. He was unavailable for comment.

SOURCE: https://bit.ly/33JDowi The Lancet Rheumatology, online July 31, 2020.