• 22 May 2020
  • 5 min 30
  • 22 May 2020
  • 5 min 30

Currently there are no approved medicines to treat COVID-19. However, there are several trials underway assessing the role of antiviral medicines, including remdesivir, in the treatment of COVID-19.

In this episode, NPS MedicineWise medical adviser and GP Dr Anna Samecki talks with CEO Adj A/Prof Steve Morris about the latest evidence for remdesivir and what this might mean for treating COVID-19.

 Read more about antiviral medicines and the treatment of COVID-19

Transcript

Voiceover:

Welcome to the NPS MedicineWise Podcast, helping health professionals stay up to date with the latest news and evidence about medicines and medical tests.

Steve Morris:

Yeah. Hi, I'm Steve Morris, CEO of NPS MedicineWise and I'm joined today by Dr. Anna Samecki, who's a GP and NPS MedicineWise medical advisor. Hi, Anna.

Anna Samecki:

Hello, Steve. How are you?

Steve Morris:

Yeah, good. Look, as many listeners may be aware, there are currently no medicines that are recommended as a treatment or prophylaxis for COVID-19. However, there are a number of medicines currently being evaluated in clinical trials, alongside the pandemic. Look, and the emphasis investigation seems to be on potential treatments that are repurposing existing medicines. So in today's podcast, we're going to focus on antivirals and in detail on one antiviral, remdesivir. So start with Anna, can you just give an overview of the potential role for existing antiviral medicines?

Anna Samecki:

Sure. So as you know, COVID-19 is caused by the SARS-CoV-2 virus, which is an RNA virus. So naturally you'd think antivirals may be effective at stopping its replication. Sure enough, there have been some promising results from preliminary in vitro studies and from some animal models, which have shown that remdesivir appears to have an inhibitory effect on coronaviruses.

Steve Morris:

Okay, in specifically more detail, what trial evidence is there for remdesivir?

Anna Samecki:

Sure. So there are a number of trials still in progress. So it will be interesting to see what those show, but if we're talking about completed and published studies, we really only have one randomized controlled trial that was published in the Lancet in April to go by. Now, that trial was a multicenter, double blind placebo controlled trial that included 10 hospitals in China and over 200 patients, the study compared intravenous remdesivir to placebo and the primary endpoint was time to clinical improvement, which was measured against a six point scale. Interestingly, remdesivir was not associated with a difference in time to clinical improvement or mortality. In addition, a number of adverse events were reported and more patients in the remdesivir group discontinued the study as a result. There was also a slightly faster time to clinical improvement in a small subset of patients who only had a short period of symptoms, so 10 days or less, but unfortunately that was not statistically significant.

Steve Morris:

So Anna, so there were essentially limitations to the current published studies?

Anna Samecki:

Well, exactly. As with the hydroxychloroquine studies we mentioned last podcast, this study in particular also had its own limitations. Unfortunately, it didn't reach its target enrollment due to public health and hospital bed restrictions and there was insufficient power to detect some differences in clinical outcomes. In addition to that, patients were also committed to continue other such as corticosteroids. So it's unclear if this had an effect on the results.

Steve Morris:

Okay, thanks Anna. In terms of other studies, what future studies are on the horizon with this medicine?

Anna Samecki:

Yeah. Look, that's another great question, Steve and I should probably mention that there is a study called the Adaptive COVID-19 Treatment Trial, or ACTT for short, which will be another randomized control trial with over a thousand patients. It hasn't been officially published yet and it's still in progress but nevertheless, an interim analysis has been released, which showed people who received remdesivir had a 31% faster time to recovery than those who took placebo. Results also suggest a survival benefit, but this was not statistically significant in that interim report.

Now, we need to remember that this is an interim report, so we'll have to wait for the full study to be published to understand all the details including safety. In addition to that, Gilead has initiated a few phase three clinical trials to evaluate the safety and efficacy of remdesivir in adults diagnosed with COVID-19. So it will be interesting to see what those show.

Steve Morris:

So for our listeners, what's the bottom line currently with remdesivir?

Anna Samecki:

So the bottom line with remdesivir is that as it stands, we only have one randomized control trial to go by and unfortunately that didn't show any evidence to use the medication in the community. So outside of clinical trials, it's currently not recommended for use.

Steve Morris:

Okay, that's pretty clear Anna. Briefly, what about some of the other antivirals?

Anna Samecki:

Sure. So you may have heard that lopinavir and ritonavir, which are medications used to treat HIV have also been researched and studied, but unfortunately, similar to remdesivir, the evidence for the use of these medications is lacking at present. That's why, again, they're not recommended for the treatment of patients with COVID-19 in the community and should only really be used in the context of clinical trials with appropriate ethics approval.

Steve Morris:

Okay, thanks Anna, I think that's clear and concise for our listeners. Look, I hope you enjoyed this podcast. Any questions or suggestions you may have for future podcasts, then please contact us via Twitter or our LinkedIn accounts. Thanks again for listening.

Voiceover:

For more information about the safe and wise use of medicines visit the NPS MedicineWise website nps.org.au.