• Tamiflu (oseltamivir) is being used in conjunction with other medicines in a number of clinical trials for patients with COVID-19 (coronavirus).
• Results of one study show Covid-19 patients treated with oseltamivir had a significantly shorter stay in the hospital and significantly lower death rate compared to the control group.
• This study did have limitations, and the authors noted that more prospective studies need to be done to clarify the clinical benefit of oseltamivir with other antiviral and combination therapies.
• Another study said that the evidence for the effectiveness of oseltamivir in treating COVID-19 was not conclusive and that more studies, especially random controlled studies, would be needed to decide if oseltamivir was effective in treating COVID-19.
• COVID-19 illness is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Tamiflu is used to treat the viruses influenza A and B, so Tamiflu may or may not be successful at treating COVID-19.

What is Tamiflu?

• Tamiflu is an antiviral medicine that belongs to the antiviral group called neuraminidase inhibitors.
• It is used treat influenza A and B

How does Tamiflu work as an antiviral medicine?

• When you become infected with a influenza A and B virus, the virus enters your cells, it makes lots of copies of itself and then the copies get released out of the cells to go and infect more cells.
• There is an enzyme (neuraminidase) on the surface of influenza A and B cells that enables the copied viruses to be released from the infected cell.
• Tamiflu blocks the enzyme from working so that the virus copies can’t be released.
• This means that the virus infection stops spreading around the body, so the infection will get better. Because Tamiflu blocks (or inhibits) the neuraminidase enzyme, so it is called a neuraminidase inhibitor
• Tamiflu will only work on SARS-CoV-2 if it has the same neuraminidase enzyme that it can block, unless it is discovered to work in an additional way.

Is Tamiflu an approved medicine by the FDA?

• Yes, Tamiflu is FDA approved for prophylaxis and treatment of acute, uncomplicated influenza A and B.
• It is not indicated for prevention or treatment of SARS-CoV-2 infection, but it is currently in clinical trials in conjunction with other treatments, to find out if Tamiflu works to reduce length of illness, complications and the rate of death in COVID-19 patients.

What happens next?

We need to wait for more trials to be completed to find out if Tamiflu reduces the length of illness, complications, and the death rate in COVID-19 patients.

The study will also be looking for any side effects or any unexpected issues that Tamiflu may cause in COVID-19 patients.

Bottom line:

• Tamiflu is a medication that is currently being trialled to treat patients with COVID-19.
• Tamiflu works by stopping the copies of influenza A and B viruses in infected cells from being released, that way they can not infect any new cells, and so stops the infection from getting worse.
• Tamiflu is currently approved by FDA for prophylaxis and treatment of acute, uncomplicated influenza A and B.
• Tamiflu is NOT currently approved for treatment of COVID-19 illness which is caused by SARS-CoV-2 coronavirus, although it is being used in clinical trials.