Fight against COVID-19 Strengthens as Gilead Launches Phase III Trial for Remdesivir

By Ruchi Jhonsa, Ph.D.

The Wuhan Coronavirus outbreak, now known as COVID-19 has taken its toll on the world since its outbreak in China last December. Found commonly in humans, camels, cattle, cats, and bats, coronavirus infection can cause mild to severe respiratory illness and symptoms include fever, cough, and shortness of breath. The current number of cases worldwide stands at 81,400 with a total death count of 2770. Early on, the patients who contracted the virus had some contact with infected persons, but recently a case of community spread (meaning, not someone who visited Asia recently) was reported in the U.S.

In an attempt to fight the virus and curb its further spread, several companies have joined the race to develop vaccines and antiviral drugs. Although vaccines would give protection against any new development of viral infection, it will not be helpful for the existing cases. In an urgent need to control the coronavirus epidemic, Gilead Sciences announced the launch of two Phase III trials of its investigational antiviral drug, Remdesivir in adults diagnosed with COVID-19. The two new Phase III studies will run in parallel with existing trials ongoing in China’s Hubei province led by the China-Japan Friendship Hospital as well as the clinical trial initiated two days back in the U.S. led by National Institute of Allergy and Infectious Diseases (NIAID). Although Remdesivir failed in the Ebola trials, it will still be the best shot for treating COVID-19 in this urgent situation, given its successful history with in vitro studies targeting SARS and MERS viruses.

According to Merdad Parsey, Gilead’s chief medical officer “Gilead’s primary focus is on rapidly determining the safety and efficacy of Remdesivir as a potential treatment for COVID-19, and this complementary array of studies helps to give us a more expansive breadth of data globally on the drug’s profile in a short amount of time. The speed with which Remdesivir has moved into clinical development for this coronavirus reflects the pressing need for treatment options and the shared commitment of industry, governments, global health organizations and healthcare providers to respond to this public health threat with the highest urgency”.

So far, the drug has not been approved or licensed for any antiviral treatments. However, outside of the clinical trials, Gilead is providing qualified patients with Remdesivir on a compassionate use basis, just in case if it works.

What is Remdesivir?

Remdesivir is an investigational broad-spectrum antiviral drug that was previously tested in humans with Ebola virus disease. The drug is an adenosine analog that competes with ATP for incorporation in the RNA and stalls the production of viral RNA. It has been shown that Remdesivir inhibits Ebola viruses with half-maximal effective concentrations in vitro. Remdesivir also showed promise in animal models for treating Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS), which are caused by other coronaviruses and therefore is believed to work against recently emerging coronavirus.

New Gilead-Sponsored Remdesivir Clinical Trials

The new Gilead clinical trial will investigate the safety and efficacy of two dosing regimens of Remdesivir administered intravenously in patients with the severe manifestation of COVID-19. Administered for a 5-day or a 10-day regime, the drug will be randomly distributed in 400 participants in a 1:1 ratio with 200mg drug at day 1 followed by a course of 100mg drug until 5 days or 10 days, along with the standard of care. The efficacy of the drug in patients will be evaluated by measuring the body temperature and oxygen saturation both of which are disturbed in COVID-19 patients.

The second study will be done to understand the drug’s safety profile and any adverse side effects associated with it. Approximately 600 patients will be enrolled in the study to receive the standard of care along with 200mg of Remdesivir on day one, followed by 100mg until day 5 or day 10, and compared to standard of care alone. The study’s success will be determined by measuring the proportion of participants in each group discharged by day 14.

After the announcement of community spread of the virus in the United States, an alarm has been raced in the community to prevent the epidemic from becoming a pandemic. The joint efforts made by the private and public sectors are commendable and they give big hope for treating COVID-19.

Related Article: Understanding the Scientific Challenges in Combating the New Coronavirus

References

1. Tchesnokov et al., 2019, Viruses
2. https://www.gilead.com/news-and-press/press-room/press-releases/2020/2/gilead-sciences-initiates-two-phase-3-studies-of-investigational-antiviral-remdesivir-for-the-treatment-of-covid-19
3. https://www.nih.gov/news-events/news-releases/nih-clinical-trial-remdesivir-treat-covid-19-begins

Author

Ruchi Jhonsa