• The technologies described in this briefing are cytokine adsorption devices. They are for reducing blood levels of cytokines in people with COVID-19 and respiratory failure.

  • The innovative aspects are that the cytokine adsorption devices reduce harmful levels of cytokines in the blood.

  • The intended place in therapy would be in addition to critical care for people with COVID-19 and respiratory failure.

  • The main points from the evidence summarised in this briefing are from a non-randomised comparative single-arm observational study and a series of case reports including 56 patients with COVID‑19 and respiratory failure. It shows that cytokine adsorption devices reduce levels of cytokines in the blood in people with COVID‑19. This may help improve lung function.

  • Key uncertainties around the evidence or technology are that most of the evidence is from company websites and is not peer reviewed. The clinical experience of using cytokine adsorbent devices in people with COVID‑19 is reported as low-quality evidence, such as case reports with small sample sizes. None of these were done in the NHS.

  • Safety issues identified are a safety notice advising that CytoSorb should not be used with nitrous oxide. Also, there is a Medical Device Alert for the Spectra Optia Apheresis System because of a risk of improper use if company instructions are not followed carefully.

  • The cost of the cytokine adsorption cartridges ranges from £450 to £1,785 per unit (excluding VAT). The cost of machines using extracorporeal circuits ranges from £10,000 up to £60,000 and are already available in NHS hospitals, but some machines are only available in specialist centres. The resource impact would be greater than standard care because the technology is intended to be used in addition to standard care.