Covid-19 treatments have been prequalified by WHO, including the three presentations. A prequalification provides assurances to countries that they are purchasing quality health products.
Before tocilizumab, the WHO has prequalified three different compositions for the steroid dexamethasone for treating Covid, as well as Gilead's antiviral remdesivir, although that prequalification has since been suspended.
Currently, tocilizumab is expensive and in short supply globally. Therefore, the WHO and partners are discussing lower prices and improved access in low- and middle-income countries with the producer, Roche.
Tocilizumab has previously been authorised mostly for the treatment of arthritis in about 120 countries. But during the pandemic, it has also been shown to suppress a dangerous "cytokine storm" -- the over-reaction of the immune system to the coronavirus.