Though not included on www.ClinicalTrials.gov as a COVID-19 trial, results of a clinical trial with Waldenstrom’s macroglobulinemia patients suggest that ibrutinib might confer protection against lung damage in hypoxic COVID-19 patients, and it may possibly improve respiratory function (165). However, the study was small and involved 6 COVID-positive patients, 5 of whom received ibrutinib at 420 mg and presented with mild symptoms that did not require hospitalization. The 6th patient on a lower dose of ibrutinib had progressive dyspnea and hypoxia and was placed on treatments in addition to ibrutinib at the lower dose, including hydroxychloroquine, azithromycin and tocilizumab. Due to worsening hypoxia, the patient was eventually placed on the higher ibrutinib dose (420 mg) and this was followed by improvement of symptoms (165).