LAUSR

The Bruton tyrosine kinase (BTK) inhibitor ibrutinib is used to treat indolent B-cell malignancies and chronic graft-versus-host disease (cGVHD). The potential for ibrutinib to abrogate pulmonary inflammatory cytokines, lung injury, and death was demonstrated in a highly relevant lethal flu animal model.1 Therefore, we sought to clarify the impact of ibrutinib in COVID19 patients. We care for 600 to 800 Waldenstrom macroglobulinemia (WM) patients each year, ;300 of whom are on a BTK inhibitor. We identified 6 patients receiving ibrutinib for WM who were diagnosed with COVID-19; these patients consented to the use of their data. Their clinical characteristics appear in Table 1. Their median age was 66 years, and 5 were on the recommended treatment doseof 420mg/d; the sixth patientwas on a reduceddose of 140 mg/d because of arthralgias. For all patients, the median time on ibrutinib was 52 months. Their median time with COVID19–related symptoms prior to diagnostic testing was 5 days, and the median time since diagnosis of COVID-19 was 22 days. All 6 patients experienced cough and fever as prodromal symptoms. The 5 patients on ibrutinib, 420mg/d, did not experience dyspnea and did not require hospitalization. Their course was marked by steady improvement, and resolution or near resolution of COVID19–related symptoms during the follow-up period.