Age 18-70 Proven Covid-19/high clinical suspicion of Covid-19 Hypoxia/respiratory compromise defined as requiring respiratory support of >2L/min of oxygen by nasal cannulae to maintain SpO2<96%. Raised inflammatory parameters: at least 2 of the following: a. Raised LDH (> 2 x ULN) b. Raised D Dimers (> 2X ULN) c. Raised CRP (>2X ULN) Females of childbearing potential have a negative pregnancy test within 7 days prior to being randomised. Participants are considered not of child bearing potential if they are surgically sterile (i.e. they have undergone a hysterectomy, bilateral tubal ligation, or bilateral oophorectomy) or they are postmenopausal

Age 18-70 Proven Covid-19/high clinical suspicion of Covid-19 Hypoxia/respiratory compromise defined as requiring respiratory support of >2L/min of oxygen by nasal cannulae to maintain SpO2<96%. Raised inflammatory parameters: at least 2 of the following: a. Raised LDH (> 2 x ULN) b. Raised D Dimers (> 2X ULN) c. Raised CRP (>2X ULN) Females of childbearing potential have a negative pregnancy test within 7 days prior to being randomised. Participants are considered not of child bearing potential if they are surgically sterile (i.e. they have undergone a hysterectomy, bilateral tubal ligation, or bilateral oophorectomy) or they are postmenopausal