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Can Leronlimab (PRO 140) be used to treat COVID-19 (coronavirus)?

Medically reviewed by Melisa Puckey, BPharm. Last updated on March 20, 2023.

Can Leronlimab (PRO 140) be used to treat COVID-19 (coronavirus)

Official answer

  • Leronlimab (PRO 140) has been used in a number of patients with COVID-19 (coronavirus) as part of two clinical trials applications that have been fast tracked by the FDA.
  • The first trial being applied for is to study the leronlimab in patients with mild to moderate COVID-19 respiratory symptoms.
  • The second trial that is being applied for will study leronlimab in patients with severe COVID-19 respiratory symptoms.

What is Leronlimab?

Humanized IgG4 monoclonal antibody (mAb)

Belongs to a group of medicine that are CCR5 antagonists.

How does Leronlimab work on COVID-19?

  • Very simply it is thought to reduce the amount of inflammation in the lungs caused by coronavirus, so it may help with breathing problems in COVID-19.
  • If you become infected with coronavirus, your immune system sends useful immune chemicals to the affected areas of the lungs to help fight the infection, which is good because this is how you recover from an infection. However in some people there is an overreaction by the immune system causing too many immune chemicals arriving in the lungs. The lungs become very inflamed and can no longer work properly, which causes severe breathing problems and can in some cases lead to death in Covid-19 patients.
  • Leronlimab works to reduce this rush of immune chemicals to the affected area, and means there is less inflammation and damage to the lungs. The actual way it does this is by blocking a protein on the white blood cells called the CCR5 receptor - which is why it is called a CCR5 antagonist (blocker).
  • The aim of leronlimab is to block the CCR5 receptor, then the body’s immune system will be able to fight the coronavirus, without the issue of excessive inflammation and other problems.

Is Leronlimab an approved medicine by the FDA?

  • No, leronlimab has not been approved by the FDA.
  • Leronlimab is in the clinical trial stage.

What other conditions is Leronlimab use for?

  • Leronlimab is used in clinical trials for the treatment of HIV/AIDS where it is being used in combination with other drug therapies to reduce the viral load.
  • Leronlimab is also being studied for use in cancer where it is hoped that it may reduce tumor metastasis.

What happens next?

We need to wait for the trials to be completed to find out how well leronlimab works to decrease any breathing and lung issues in COVID-19 and whether it speeds up patients recovery.

The studies will also be looking for any side effects or any unexpected issues that may reduce leronlimab usefulness in COVID-19 patients

Bottom line

  • Leronlimab is one medication that is currently being trialled to treat patients with respiratory or breathing complications from COVID-19.
  • Leronlimab is thought to decrease the ‘cytokine storm’ or excessive immune response within the lungs in patients with COVID-19.
  • Leronlimab is not currently approved by FDA and is in the clinical trial stage of development.

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