Australia’s treatment of Covid-19 patients has improved with doctors claiming new drug options and increased experience with the virus may help ease the burden on hospitals.
In August, Australia’s drug regulator, the Therapeutic Goods Administration, approved a novel antibody treatment called sotrovimab. The drug will prevent those most at risk from developing severe disease.
Director of infectious diseases at Mater Health Services, Prof Paul Griffin, said it is the first treatment for people that have mild Covid, with other treatments to date focused on those with critical disease in hospital.
“Sotrovimab is an antibody treatment, and one that’s been shown in good clinical trials to have a dramatic impact in reducing people’s probability of progressing to severe disease,” Griffin said. “If there’s someone who’s high risk at developing severe symptoms, it can be given to them. It does need to be given early, before people are very unwell, but in those people it stops very significant progression through to severe disease.”
The drug works by binding to the virus’s spike protein. This protein is essential to the virus’s ability to enter cells and continue to replicate and spread throughout the body. Sotrovimab blocks this process.
Griffin said sotrovimab is already being given in Australia to vulnerable people with health risks aged over 55, or those under 55 with significant comorbidities like diabetes or kidney disease.
“Those people obviously are at very significant risk of getting severely unwell with Covid,” he said. “In the first five days, before they get very sick and before they need oxygen, that antibody can reduce their chance of progressing to needing hospitalisation.
“It is being used now, and is modifying the disease trajectory in the highest risk people. Unfortunately there are still some supply constraints around this medication, but it will help a lot, as until now we haven’t had any highly effective, specifically antiviral medications.”
It will have the flow-on effect of reducing the strain on hospitals, especially intensive care units, he said.
“This drug will mean even if we have a lot of Covid cases, if we target the drug at those most at risk we’ll have fewer people clogging up the hospital system and utilising those precious limited resources and so it could, potentially, make the virus much more manageable.”
Griffin said nurses and physicians were also now much more experienced at treating severe cases. Since last year, most critically ill people on a ventilator have been given a corticosteroid called dexamethasone, as it appears to reduce the risk of death. There is now enough evidence to indicate the benefits of using it to treat Covid almost always outweigh the risk of harm.
It is not recommended for those with mild or moderate disease. The drug appears to dampen the over-active immune response seen in some patients that causes excessive inflammation and severe symptoms. It can also be used in ventilated children.
Other sophisticated anti-inflammatory medicines are being trialled in ventilated patients, such as tocilizumab and baricitinib, though there is a critical shortage of the former in Australia. These drugs “probably” reduce the risk of death in critical patients, but more research is needed, Australian clinical care guidelines say.
The guidelines also conditionally support use of the antiviral remdesivir in hospitalised adults with moderate to severe Covid-19, who do not require ventilation as it “probably” reduces the risk of death. The guidelines do not recommend it be used in adults who do require ventilation.
This differs to the World Health Organization guidelines, which recommends against the use of remdesivir in hospitalised patients, irrespective of disease severity. The difference in recommendations comes down to differences in how WHO and Australian regulators analyse data, but Griffin said clinical experience with remdesivir shows it has overall underwhelming results.
“But the addition of anti inflammatory medicines like dexamethasone and tocilizumab have certainly made a difference,” he said.
“Over time though, I think there will be lots more treatments added for Covid-19. We would like to see a highly-active, Covid-19-specific antiviral that could be used orally. That would be a highly desirable tool which we don’t have yet. But lots of promising research is happening and in the near future, I expect we will have a larger range of treatments available.
“In the meantime we have already come a long way in our understanding how the disease progresses, and with more people vaccinated combined and the addition of sotrovimab, the situation is being helped a lot. ”
With health professionals becoming more adept at treating Covid and treatments being approved, Griffin said it was distressing to hear about people using and advocating unproven treatments such as ivermectin, an anti-parasitic medication currently only being given to Covid-19 patients in Australia as part of tightly controlled clinical trials.
A man was hospitalised in Sydney after self-administering ivermectin, and the TGA reported concern over increased importation and prescribing of the drug.
“I’m certainly aware of the strong push to get ivermectin, and it’s frustrating,” Griffin said. “It’s not a risk-free medication and people are often using sub-standard preparations designed for animals. It also means potentially those people are less likely to seek out evidence-based care, and they’re less likely to present for testing or come to hospital for the treatments we now have.
“I think people want to believe there’s some kind of conspiracy that we’re concealing or withholding effective treatments when in fact there is a lot of work going into research.”
The president of the Royal Australian College of General Practitioners, Dr Karen Price, said the attraction of unproven and potentially harmful treatments was unsurprising.
“In times of heightened anxiety, people want a fast solution that will keep them and their loved ones safe,” she said.
“They may suspend any doubt they have and be lured in by false promises via social media or prominent public figures doing all they can to draw attention to themselves. I wish I could tell them that ivermectin will protect them from Covid-19 but that simply isn’t the case.”
She said medical treatments require high levels of testing and retesting.
“Ivermectin has not passed this standard, she said. “In contrast, sotrovimab is an example of a new drug for the treatment of Covid-19 that has passed through the rigorous testing safety procedures of the Therapeutic Goods Administration.”
Price said even more so than treatments, the best protection against the virus is vaccination.
“Tell your friends and family to get vaccinated too, abide by any Covid-19 restrictions in place and remember that your GP is always there to help,” she said. “We won’t offer untested treatments featured on your Facebook news feed, but we will be there to give you your Covid-19 vaccine and treat you for any other health concerns you may have.”