In patients not on mechanical ventilation, the risk of mechanical ventilation or death is reduced by 21 per cent, compared to the use of corticosteroids alone.

These are the first drugs found to be effective against Covid-19 since corticosteroids were recommended by WHO in September 2020.

Patients severely or critically ill with Covid-19 often suffer from an overreaction of the immune system, which can be very harmful to the patient's health. Interleukin-6 blocking drugs -- tocilizumab and sarilumab–act to suppress this overreaction.

"These drugs offer hope for patients and families who are suffering from the devastating impact of severe and critical Covid-19. But IL-6 receptor blockers remain inaccessible and unaffordable for the majority of the world," WHO director general Tedros Adhanom Ghebreyesus said in a statement.

"The inequitable distribution of vaccines means that people in low- and middle-income countries are most susceptible to severe forms of Covid-19. So, the greatest need for these drugs is in countries that currently have the least access. We must urgently change this."

To increase access and affordability of these life-saving products, the WHO called on manufacturers to reduce prices and make supplies available to low- and middle-income countries, especially where Covid-19 is surging.

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