Preclinical data on remdesivir indicates that the drug may have potential as a treatment against the new coronavirus COVID-19. Remdesivir is one of the few drugs that has a realistic prospect of helping patients during the outbreak.
The US biotech company Gilead has ramped up the production of its experimental drug remdesivir, which has become a focal point for expectations for a successful coronavirus cure. In preparation for increasing needs of COVID-19 medicines, Gilead has accelerated manufacturing timelines to increase supply as fast as possible.
According to Gilead, the first clinical trial of the antiviral medicine remdesivir in COVID-19 patients is due to report its findings next month.
Since the coronavirus epidemic occurred, in the absence of any existing COVID-19 medicines, about 300 separate studies were conducted into different drugs and experimental therapies.
Remdesivir treatment for COVID-19
Remdesivir looks to have established itself as the champion drug, in the minds of many. Originally developed by Gilead to treat Ebola, it is now one of the very few medications that have a fair chance of treating COVID-19 patients in the near future.
Timothy Sheahan, a virologist who has studied remdesivir at the University of North Carolina, Chapel Hill, stated:
“As a therapy, it could potentially help make people’s disease less severe, save lives for those hospitalised, and be used prophylactically for hospital workers and perhaps even in the community to limit spread out there,” adding that the wider use of the drug in the coronavirus epidemic was entirely dependant on its success in the clinical trials.
While awaiting these findings, physicians in the US, China and Italy are already compassionately using remdesivir for the treatment of a small number of COVID-19 patients in critical conditions.
The first COVID-19 patient in the US to be treated with remdesivir, a 35-year-old male, was healed in Snohomish County, Washington. But complete trials are required to determine whether the medication decreases symptom severity and, importantly, mortality rates.
David Ho, a professor at the University of Columbia, and an infectious disease expert, believes that the most promising candidate is Remdesivir. He stated:
“In New York, we have one case in our hospital right now and we’re trying to access that drug for our critically ill patient..”
His team was waiting to hear back from Gilead whether the request for compassionate use was approved by the hospital. Doctors in the UK were advised there is a limited supply of Remdesivir upon request.
Remedesivir multiple clinical trials
The medicine is being tested in multiple clinical trials, the first two of which began to recruit participants in China at the beginning of February and another is enrolling patients in the United States.
Two new trials are scheduled to be conducted this month in Asia and other countries with a high number of COVID-19 patients, comparing two different doses of the remdesivir medication and expected to report as early as May.
Gilead declared it increased manufacturing “in preparation of potential future uses” despite not knowing whether the trials will prove that the drug is safe and effective in treating patients with COVID-19.
Other experimental COVID-19 treatments
Certain drugs being screened include the Kaletra anti-HIV medication and other medications commonly used for treating hepatitis and malaria.
Kaletra is a combo medicine used to maintain HIV. The drug combines Lopinavir, which blocks HIV replication, and Ritonavir, a drug which boosts the durability of Lopinavir in the bloodstream by preventing the body from breaking it down too easily.
But virologist Timothy Sheahan stated he did not believe Kaletra will be effective against the virus:
“My personal feeling is that things like Kaletra are not going to be efficacious. I’m sceptical that a very specific drug for HIV protease is going to work against a coronavirus. We did head-to-head studies in mice and cells comparing remdesivir and lopinavir, and lopinavir didn’t work as well.
In spite that the “chances of finding something very useful” are low according to Ho as well, he believes it was still worth pursuing trials on Kaletra and hepatitis drugs. But the large volume of trials currently underway, some involving “wacky” therapies that appeared to have little scientific foundation, was proving to be unhelpful. Ho said further:
“It’s pretty haphazard,” … “Gilead is trying to do two different trials in China, but they’re competing with all these other things going on. They’re actually having some trouble with recruitment now that the case load is decreasing.”
Remdesivir effectiveness against a range of coronaviruses
Remdesivir inhibits the ability of the virus to multiply in the body, and operated against two more deadly coronaviruses, Sars and Mers in animal studies, particularly when it is administered soon after symptoms appear.
It has also shown effectiveness when used against a wider range of coronaviruses, including those triggering the common cold, and others infecting bats and pigs.
Because the same replication process occurs in all coronaviruses, there are high hopes that if the drug works on one, it will work on all coronavirus strains. Sheahan added:
For this to be useful you have to really catch the virus as it’s ramping up replication in someone’s body and not after too much damage has been done,…”. “If you can intervene prior to the virus topping out, there’s a pretty good chance you can improve outcomes and potentially save people’s lives. For Sars and Mers, in upper airway, virus peaks a week to 10 days after the onset of symptoms, so you probably have five to 10 days to intervene after you start to feel crummy.”
Whilst more than one hundred thousand people are currently infected with COVID-19, there are many more who could benefit from a medication that could protect them from infection pre-emptively. A number of pharmaceutical and biotechnology companies are racing to develop a vaccine.