Inhaled ciclesonide for SARS-CoV-2 in clinical trials

In some people, SARS-CoV-2 infection can cause inflammation of the lungs and pneumonia. A large randomized clinical trial has found that the steroid dexamethasone can reduce the risk of death in people hospitalized with COVID-19 who are also receiving respiratory support (supplementary oxygen, invasive mechanical ventilation).

Researchers are continuing to experiment with dexamethasone and other steroids in people with COVID-19. One steroid of interest is ciclesonide, which is sold in the following formulations:

  • Omaris – a nasal spray used for relieving runny nose, sneezing and other symptoms that can accompany seasonal allergies
  • Alvesco – an aerosol formulation that is inhaled through the mouth and used to treat symptoms of asthma (difficulty breathing, wheezing)

Lab experiments with cells suggest that ciclesonide has potent antiviral activity against SARS-CoV-2.

Experiments in people with asthma in the pre-COVID-19 era suggest that when inhaled most aerosolized ciclesonide stays in the lungs.

Reports suggest that ciclesonide has been used as part of the successful treatment of some cases of COVID-19-related pneumonia. The totality of the evidence (lab studies and case reports) indicates that ciclesonide could be a candidate for testing to help prevent or even treat COVID-19. Clinical trials of this drug in people with COVID-19 are underway at McGill University in Montreal and in South Korea and Sweden.

—Sean R. Hosein


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  2. RECOVERY Collaborative Group. Dexamethasone in hospitalized patients with Covid-19. New England Journal of Medicine. 2021 Feb 25;384(8):693-704.
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