Tocilizumab,
originally designed for rheumatoid arthritis,
reduces Covid-19 ventilator deaths around 45%

https://medicalxpress.com/news/2020-07-drug-linked-dying-covid-patients.html

Sample quote

The ASP group developed treatment guidelines provided to Michigan Medicine physicians in mid-March that identified tocilizumab as a potentially beneficial therapy for the most severely ill COVID-19 patients. Those guidelines also pointed out its risks and the lack of evidence for its use in COVID-19, and recommended a dose of 8 milligrams per kilogram.

This led some physicians to choose to use it, while others did not—setting the stage inadvertently for a natural comparison.
snip
Pogue notes that a single dose of tocilizumab is roughly 100 times more expensive than a course of
dexamethasone. ( which reduces Covid-19 ventilator deaths by 20%)

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