[25] In 2011, the US Food and Drug Administration (FDA) approved tocilizumab for the treatment of active systemic juvenile idiopathic arthritis.

[28] On 30 August 2017, the FDA approved tocilizumab for cytokine release syndrome, a side effect of CAR-T cell therapies.

[29] In June 2021, the US Food and Drug Administration (FDA) issued an emergency use authorization (EUA) for tocilizumab for the treatment of COVID‑19 in hospitalized people aged two years of age and older who are receiving systemic corticosteroids and require supplemental oxygen, non-invasive or invasive mechanical ventilation, or extracorporeal membrane oxygenation (ECMO).

[33] Among the less common side effects were dizziness, various infections, as well as reactions of the skin and mucosae like mild rashes, gastritis and mouth ulcer.

A possible mechanism is that the elevated IL-6 levels of patients with rheumatoid arthritis suppress the biosynthesis of various cytochrome P450 enzymes, notably CYP1A2, CYP2C9, CYP2C19 and CYP3A4.

[38] In further studies, it was effective and generally well tolerated when administered either as monotherapy or in combination with conventional DMARDs in adult patients with moderate to severe rheumatoid arthritis.

[22] In January 2009, the drug was approved by the European Medicines Agency (EMA) as Roactemra for the treatment of rheumatoid arthritis under the mentioned restrictions.

[32] In September 2021, Indian pharmaceutical firm Hetero obtained emergency use approval from the country's health authority, Drugs Controller General of India (DCGI), to produce a generic version of tocilizumab to treat COVID‑19 in adults.

[51] In December 2021, tocilizumab was granted a provisional approval by the Australian regulator, Therapeutic Goods Administration, for treatment of adults.

[55] Tocilizumab is under evaluation in a multicenter clinical trial (ALL-IN) for the prevention of acute cellular rejection in status post heart transplant patients.

[57] A 2021 meta-analysis of randomized controlled trials found that, while tocilizumab does not show significant benefits on survival, it could play a role in preventing progression to intensive care and mechanical ventilation.

][59] Early case reports suggest tocilizumab might be effective in otherwise refractory neuromyelitis optica (NMO, Devic's disease).

[60][61][62][63] Two small studies found tocilizumab to be beneficial in endocrine ophthalmopathy (Graves' orbitopathy) that is refractory to corticosteroid treatment.