There have been a number of studies published on the use of Interleukin-6 inhibitors in the management of COVID-19 pneumonitis (linked below), which have been largely inconclusive. However, the findings from the immunomodulatory domain of the REMAP-CAP study (currently in pre-print, linked below) shows an improved survival outcome when Interleukin-6 inhibitors are used in the treatment of severe COVID pneumonitis. There is also a trend towards increased likelihood of discharge from ICU and hospital.
The inclusion criteria for these drugs include:
- COVID-19 infection is confirmed
- Admitted to ICU with severe pneumonia requiring respiratory support
- Less than 24-hours since ICU admission
The exclusion criteria include:
- More than 24 hours since ICU admission
- Already receiving any of the immune modulating drugs for treatment
- In another trial
- Known hypersensitivity
- Co-existing infection that might be worsened by tocilizumab or sarilumab
- A baseline ALT or AST more than 5 times the upper limit of normal
- A baseline platelet count of less than 50 x 109/L
- A baseline absolute neutrophil count of less than 2 x 109/L
- A pre-existing condition or treatment resulting in ongoing immunosuppression
It is still vitally important that if patients do not meet the inclusion criteria for these drugs, they are considered for recruitment on the RECOVERY study.
The dosing of Tocilizumab is given at 8mg/kg, up to a maximum dose of 800mg. There is an option to repeat the dose after 12-24 hours if there has been no significant clinical improvement after the first dose. Sarilumab is given as a 400mg once-only intravenous infusion. There is an interim position statement (linked below) which enables clinicians to administer these drugs.
On administration of Interleukin-6 inhibitors, the patient’s CRP response is abolished, so other biomarkers should be used when considering a secondary bacterial infection.