As the world awaits the development of a vaccine for the novel coronavirus causing Covid-19, reports in the past week of successful treatment of severely ill patients at a Chicago hospital with the antiviral medicine Remdesivir were headlined in the US and caused a bounce on global sharemarkets.
Remdesivir was one of the first medicines identified in lab tests as having the potential to impact SARS-CoV-2. Results from US biotechnology firm Gilead Science’s clinical trials have been eagerly expected as the world looks for positive outcomes which could lead to fast approvals by the Food and Drug Administration and other regulatory agencies.
If safe and effective, it could become the first approved treatment against the disease.
The University of Chicago Medicine recruited 125 people with Covid-19 into Gilead’s two Phase 3 clinical trials. Of those people, 113 had severe disease.
All the patients have been treated with daily infusions of Remdesivir. Rapid recoveries were observed in fever and respiratory symptoms, with nearly all patients discharged in less than a week,
The outcomes offer only a snapshot of Remdesivir’s effectiveness. The same trials are being run concurrently at other institutions and it’s impossible to determine the full study results with any certainty.
“The best news is that most of our patients have already been discharged, which is great. We’ve only had two patients perish,” said Kathleen Mullane, the University of Chicago infectious disease specialist overseeing the remdesivir studies for the hospital.
“It’s always hard,” she said, because the severe trial doesn’t include a placebo group for comparison.
“But certainly when we start [the] drug, we see fever curves falling. Fever is now not a requirement for people to go on trial, we do see when patients do come in with high fevers, they do [reduce] quite quickly. We have seen people come off ventilators a day after starting therapy. So, in that realm, overall our patients have done very well.”
In a statement on Thursday, Gilead said:
“What we can say at this stage is that we look forward to data from ongoing studies becoming available.”
Gilead had said earlier to expect results for its trial involving severe cases this month.
Mullane indicated that data for the first 400 patients in the study would be “locked” by Gilead on Thursday, meaning that results could come any day.
Point of Order, in a review back on March 16 of work being done on finding treatments including antiviral drugs against Cobid-19 recorded:
“The most advanced of these appears to be California-based Gilead Sciences, which for the past few years has been developing Remdesivir, an anti-viral with promising results in lab and animal studies against SARS, MERS, Ebola and other infectious diseases, including Covid-19”.
Gilead said it is expanding its clinical trials of Remdesivir as a possible coronavirus treatment involving
“ … approximately 1,000 patients at medical centres primarily across Asian countries, as well as other countries globally with high numbers of diagnosed cases,”
The drug is still experimental, not yet approved to treat any disease. Studies of infected mice and monkeys have suggested that Remdesivir can fight coronaviruses, and it appeared to cause few side effects when it was tested in patients with Ebola, although it did not work well against that virus.
Point of Order noted at that time researchers were trying to determine which patients Remdesivir might help most, by giving the drug to people who are severely ill and also some who are not as sick. They also hope to find out how long a course of treatment is needed.
“Because it’s an outbreak and we try to target people who stand to have a clear benefit, first we target people who are symptomatic, so they are hospitalised,” Dr Diana Brainard, Gilead’s senior vice president for HIV and emerging viruses, said.
“There is a precedent in respiratory viral infections, that the earlier you treat, the better, and there may be a threshold beyond which it doesn’t make sense to treat.”
On the other hand, she said, if the drug does help severely ill patients, that could be its greatest impact.
Another goal of the new trial is to find out if a shorter course of treatment will work. If a shorter duration does work, she said,
“ … that automatically doubles the drug supply.”
Faster treatment would also get patients out of the hospital faster, lessen their exposure to hospital-based infections and make room for more patients, she explained.
One of the new trials will include 400 severely ill patients, who will be picked at random to receive either five days or 10 days of treatment with the drug, which must be given intravenously.
The other trial will involve 600 moderately ill patients. Along with standard care — oxygen if needed, fluids, medicines for pain and fever — a third will receive the drug for five days, and a third for 10 days. The last third will receive standard care alone.
A World Health Organisation assessment from February described Remdesivir as the “most promising candidate” against Covid-19.